feat: implement multi-tenancy support across knowledge services and normalize TenantId to string type.

GEMINI.md

@@ -34,4 +34,9 @@ version: 1.0
 1. **Verification-Led:** Plan and define tests/verification steps *before* writing feature code.
 2. **Step-by-Step Execution:** Break complex tasks into manageable, verifiable chunks.
 3. **Layer Integrity:** Always check for illegal cross-layer dependencies (e.g., Application depending on Infrastructure).
+4. **Mandatory Build Gate:** After **every** code change, run `dotnet build` on the full solution. The agent MUST NOT proceed or report completion if there are any `error CS*` compiler errors. All build errors must be resolved before moving to the next step.
+
+> [!IMPORTANT]
+> **Build command:** `dotnet build NexusReader.slnx --no-restore`  
+> Run from the solution root `/home/mjasin/Projekty/ejajBook`. Build warnings are acceptable; errors are not.
 

backlog-code-review.md

@@ -0,0 +1,156 @@
+# 🔍 NexusReader Code Review Backlog
+
+## 🔴 CRITICAL — Fix Before Next Release
+
+- **Status:** ✅ Resolved (2026-05-03)
+- **Implementation:** Removed `AddMediatR` from `AddApplication()` and `AddInfrastructure()`. Unified registration in Host (`Program.cs`, `MauiProgram.cs`). Added `IInfrastructureMarker` and a startup validation check in `Web.New` that throws `InvalidOperationException` if `AddInfrastructure` is missing.
+- **DoD:** Application fails fast with a clear error if `AddInfrastructure()` is omitted.
+
+---
+
+- **Status:** ✅ Resolved (2026-05-03)
+- **Implementation:** Added `VerifyGroundednessAsync` to `IKnowledgeService` and implemented it in `KnowledgeService` (Infrastructure). Updated `VerifyGroundednessCommandHandler` in Application to inject `IKnowledgeService` instead of `IChatClient`.
+- **DoD:** No `IChatClient` or `IEmbeddingGenerator` references remain in `NexusReader.Application`.
+
+---
+
+- **Status:** ✅ Resolved (2026-05-03)
+- **Implementation:** Threaded `tenantId` through all `IKnowledgeService` methods and `ProcessKnowledgeUnitsAsync`. Scoped `SemanticKnowledgeCache` and `KnowledgeUnit` lookups/writes to the provided `tenantId`. Updated API endpoints in `Program.cs` and `WasmKnowledgeService` to pass the authenticated user's `TenantId`.
+- **DoD:** No hardcoded `"global"` TenantId in write paths. Extracted units are always scoped to the caller's tenant.
+
+---
+
+- **Status:** ✅ Resolved (2026-05-03)
+- **Implementation:** Changed `NexusUser.TenantId` from `Guid` to `string`. All entities now use `string` for `TenantId`, allowing the use of `"global"` as a sentinel value.
+- **DoD:** All entities use the same `TenantId` type. All query filters are consistent.
+
+---
+
+## 🟠 MAJOR — High Priority Fixes
+
+### [MJ-01] Missing Exception Handling in `EpubService`
+
+- **File:** `Infrastructure/Services/EpubService.cs:45`
+- **Problem:** The service uses raw `ZipArchive` operations without try-catch blocks. Corrupt EPUB files will crash the circuit instead of returning a `Result.Fail`.
+- **Action:** Wrap the extraction logic in a try-catch and return `Result.Fail<EpubContent>(ex.Message)`.
+- **DoD:** Uploading a renamed `.txt` as `.epub` returns a user-friendly error instead of a 500 error.
+
+---
+
+### [MJ-02] Hardcoded Pricing & Limits in Stripe Logic
+
+- **File:** `Web.New/Program.cs:298`
+- **Problem:** Subscription limits (50k tokens for Pro) are hardcoded in the webhook handler. Changing prices or limits requires a code redeploy.
+- **Action:** Move limits to `appsettings.json` or a `SubscriptionPlan` domain entity. Use `IOptions<SubscriptionSettings>` in the handler.
+- **DoD:** Limits can be changed via configuration without rebuilding the app.
+
+---
+
+### [MJ-03] Knowledge Graph: Circular Dependency Potential
+
+- **File:** `UI.Shared/Services/KnowledgeGraphService.cs`
+- **Problem:** The service manages its own state but is injected as `Scoped`. If multiple components use it, they share the same graph state, which might lead to race conditions during navigation.
+- **Action:** Ensure the service is either stateless (returning data) or implement a `Clear()` method called on `OnInitialized`.
+- **DoD:** Navigating between two different books correctly clears the graph.
+
+---
+
+### [MJ-04] Insecure `Profile` Endpoint Exposes Internal IDs
+
+- **File:** `Web.New/Program.cs:366`
+- **Problem:** The `/identity/profile` endpoint returns the raw `TenantId` and internal database IDs in the JSON response.
+- **Action:** Create a `UserProfileDto` and use Mapster to exclude internal metadata.
+- **DoD:** Sensitive internal GUIDs/IDs are not visible in the browser's Network tab.
+
+---
+
+### [MJ-05] Missing Database Index for Multi-Tenancy
+
+- **Problem:** `TenantId` is used in almost every query (KnowledgeUnits, Cache, Users) but lacks a database index. As data grows, retrieval will slow down significantly (O(N) vs O(log N)).
+- **Action:** Add `HasIndex(x => x.TenantId)` to the `AppDbContext` configuration for all relevant entities.
+- **DoD:** EF Migration generated with `CREATE INDEX` for `TenantId`.
+
+---
+
+### [MJ-06] KM-RAG: Link Integrity is Not Validated
+
+- **File:** `Infrastructure/Services/KnowledgeService.cs:208`
+- **Problem:** When processing `KnowledgeUnitLink`, the service assumes both `Source` and `Target` units exist in the DB. If AI returns a link to a non-existent node, the DB insert will fail (foreign key violation).
+- **Action:** Add a check to verify both units exist or are being created in the same batch before adding the link.
+- **DoD:** Broken links from AI are logged as warnings and skipped, not causing a total failure.
+
+---
+
+### [MJ-07] Ebook Entity Missing Tenant Isolation
+
+- **File:** `Domain/Entities/Ebook.cs`
+- **Problem:** The `Ebook` entity lacks a `TenantId` property. All uploaded books are visible to all users if the ID is guessed.
+- **Action:** Add `TenantId` to `Ebook` and filter all queries in `EpubService`.
+- **DoD:** User A cannot see User B's books.
+
+---
+
+### [MJ-08] QuizResults Missing Tenant Isolation
+
+- **File:** `Domain/Entities/QuizResult.cs`
+- **Problem:** Similar to ebooks, quiz results are not scoped to a tenant.
+- **Action:** Add `TenantId` to `QuizResult`.
+- **DoD:** Results are correctly partitioned.
+
+---
+
+## 🟡 MINOR — Technical Debt & UX
+
+### [MN-01] Missing Logging in `KnowledgeCoordinator`
+- **Action:** Add `ILogger<KnowledgeCoordinator>` and log successful/failed extraction steps.
+
+### [MN-02] Hardcoded "Gemini-1.5-Flash" in Domain
+- **File:** `Domain/Entities/SemanticKnowledgeCache.cs:20`
+- **Action:** Move the default model ID to a constant in `AiSettings`.
+
+### [MN-03] UI: Shimmer Effect Lack Animation
+- **File:** `UI.Shared/Components/Molecules/GroundednessBadge.razor`
+- **Action:** Add `@keyframes` for the shimmer effect in CSS.
+
+### [MN-04] Identity: Google Callback Lack Error Handling
+- **File:** `Web.New/Program.cs:340`
+- **Action:** Better UI feedback when `ExternalLoginInfo` is null.
+
+### [MN-05] Tokenizer Initialization is Expensive
+- **File:** `Infrastructure/Services/KnowledgeService.cs:43`
+- **Action:** Make `_tokenizer` static or Singleton to avoid recreating it per request.
+
+### [MN-06] Mapster: Global Configuration Check
+- **Action:** Ensure `TypeAdapterConfig.GlobalSettings.Scan(...)` is only called once.
+
+### [MN-07] SignalR: Missing Reconnection Logic
+- **Action:** Implement `hubConnection.OnReconnected` in `SyncService.cs`.
+
+### [MN-08] CSS: Z-Index Consistency
+- **Action:** Define a `z-index` scale in `index.css`.
+
+### [MN-09] SEO: Missing Meta Descriptions
+- **Action:** Update `App.razor` with dynamic meta tags.
+
+### [MN-10] Performance: Large EPUB Parsing
+- **Action:** Implement streaming extraction for EPUBs over 10MB.
+
+---
+
+## 🧪 TESTING — Coverage Gaps
+
+### [TEST-01] Integration Tests for KM-RAG Retrieval
+- **Action:** Create `tests/NexusReader.IntegrationTests`.
+- **Scenario:** Ingest a document, then verify that `GetRelevantContext` returns the correct snippets with tenant isolation active.
+
+---
+
+## 📊 Summary Table
+
+| Severity | Count | Status |
+|---|---|---|
+| 🔴 Critical | 4 | 4 resolved |
+| 🟠 Major | 8 | Unresolved |
+| 🟡 Minor | 10 | Unresolved |
+| 🧪 Tests | 1 | Unresolved |
+| **Total** | **23** | **4 resolved** |

src/NexusReader.Application/Abstractions/Services/IKnowledgeService.cs

@@ -5,10 +5,13 @@ namespace NexusReader.Application.Abstractions.Services;
 
 public interface IKnowledgeService
 {
-    Task<Result<KnowledgePacket>> GetKnowledgeAsync(string text, CancellationToken cancellationToken = default);
-    Task<Result<KnowledgePacket>> GetGraphDataAsync(string text, CancellationToken cancellationToken = default);
-    Task<Result<KnowledgePacket>> GetKnowledgeMapAsync(string text, CancellationToken cancellationToken = default);
-    Task<Result<KnowledgePacket>> GetSummaryAndQuizAsync(string text, CancellationToken cancellationToken = default);
+    Task<Result<KnowledgePacket>> GetKnowledgeAsync(string text, string tenantId, CancellationToken cancellationToken = default);
+    Task<Result<KnowledgePacket>> GetGraphDataAsync(string text, string tenantId, CancellationToken cancellationToken = default);
+    Task<Result<KnowledgePacket>> GetKnowledgeMapAsync(string text, string tenantId, CancellationToken cancellationToken = default);
+    Task<Result<KnowledgePacket>> GetSummaryAndQuizAsync(string text, string tenantId, CancellationToken cancellationToken = default);
     Task<Result<List<RelevantContext>>> GetRelevantContextAsync(string query, string tenantId, CancellationToken cancellationToken = default);
+    Task<Result<GroundednessResult>> VerifyGroundednessAsync(string answer, string context, string tenantId, CancellationToken cancellationToken = default);
     Task<Result> ClearCacheAsync(CancellationToken cancellationToken = default);
 }
+
+public record GroundednessResult(float Score, string Rationale, bool IsGrounded);

src/NexusReader.Application/Commands/AI/VerifyGroundednessCommand.cs

@@ -1,51 +1,22 @@
 using FluentResults;
 using MediatR;
-using Microsoft.Extensions.AI;
+using NexusReader.Application.Abstractions.Services;
 
 namespace NexusReader.Application.Commands.AI;
 
-public record VerifyGroundednessCommand(string Answer, string Context) : IRequest<Result<GroundednessResult>>;
-
-public record GroundednessResult(float Score, string Rationale, bool IsGrounded);
+public record VerifyGroundednessCommand(string Answer, string Context, string TenantId) : IRequest<Result<GroundednessResult>>;
 
 public class VerifyGroundednessCommandHandler : IRequestHandler<VerifyGroundednessCommand, Result<GroundednessResult>>
 {
-    private readonly IChatClient _chatClient;
+    private readonly IKnowledgeService _knowledgeService;
 
-    public VerifyGroundednessCommandHandler(IChatClient chatClient)
+    public VerifyGroundednessCommandHandler(IKnowledgeService knowledgeService)
     {
-        _chatClient = chatClient;
+        _knowledgeService = knowledgeService;
     }
 
     public async Task<Result<GroundednessResult>> Handle(VerifyGroundednessCommand request, CancellationToken cancellationToken)
     {
-        var systemPrompt = @"
-        You are a Fact-Checking AI. Evaluate if the 'Answer' is supported by the 'Context'.
-        Rate the groundedness from 0.0 to 1.0.
-        Return ONLY a JSON object: { ""score"": 0.9, ""rationale"": ""string"", ""isGrounded"": true }
-        ";
-
-        var userPrompt = $"Context: {request.Context}\n\nAnswer: {request.Answer}";
-
-        try
-        {
-            var response = await _chatClient.GetResponseAsync(new List<ChatMessage>
-            {
-                new ChatMessage(ChatRole.System, systemPrompt),
-                new ChatMessage(ChatRole.User, userPrompt)
-            }, cancellationToken: cancellationToken);
-
-            var rawJson = response.Text?.Trim() ?? "{}";
-            // Simple cleanup if needed
-            rawJson = rawJson.Replace("```json", "").Replace("```", "").Trim();
-            
-            var result = System.Text.Json.JsonSerializer.Deserialize<GroundednessResult>(rawJson, new System.Text.Json.JsonSerializerOptions { PropertyNameCaseInsensitive = true });
-            
-            return result != null ? Result.Ok(result) : Result.Fail("Failed to parse groundedness result");
-        }
-        catch (Exception ex)
-        {
-            return Result.Fail(new Error("Failed to verify groundedness").CausedBy(ex));
-        }
+        return await _knowledgeService.VerifyGroundednessAsync(request.Answer, request.Context, request.TenantId, cancellationToken);
     }
 }

src/NexusReader.Application/DependencyInjection.cs

@@ -9,11 +9,8 @@ public static class DependencyInjection
     {
         services.AddMapsterConfiguration();
 
-        services.AddMediatR(config => 
-        {
-            config.RegisterServicesFromAssembly(typeof(DependencyInjection).Assembly);
-        });
-
         return services;
     }
+
+    public static System.Reflection.Assembly Assembly => typeof(DependencyInjection).Assembly;
 }

src/NexusReader.Application/Queries/Graph/GetKnowledgeGraphQuery.cs

@@ -3,5 +3,6 @@ using NexusReader.Application.Abstractions.Messaging;
 namespace NexusReader.Application.Queries.Graph;
 
 /// <param name="Text">Chapter or page content to extract the graph from.</param>
-public record GetKnowledgeGraphQuery(string Text) : IQuery<GraphDataDto>;
+/// <param name="TenantId">Tenant scope for knowledge extraction and caching.</param>
+public record GetKnowledgeGraphQuery(string Text, string TenantId) : IQuery<GraphDataDto>;
 

src/NexusReader.Application/Queries/Graph/GetKnowledgeGraphQueryHandler.cs

@@ -18,20 +18,13 @@ internal sealed class GetKnowledgeGraphQueryHandler : IQueryHandler<GetKnowledge
         if (string.IsNullOrWhiteSpace(request.Text))
             return Result.Ok(new GraphDataDto());
 
-        var result = await _knowledgeService.GetGraphDataAsync(request.Text, cancellationToken);
+        var result = await _knowledgeService.GetGraphDataAsync(request.Text, request.TenantId, cancellationToken);
 
         if (result.IsFailed)
             return Result.Fail<GraphDataDto>(result.Errors);
 
         var graph = result.Value.Graph;
 
-        if (graph is null)
-            return Result.Ok(new GraphDataDto());
-
-        if (graph is null)
-            return Result.Ok(new GraphDataDto());
-            
-        return Result.Ok(graph);
+        return graph is null ? Result.Ok(new GraphDataDto()) : Result.Ok(graph);
     }
 }
-

src/NexusReader.Domain/Entities/NexusUser.cs

@@ -1,4 +1,5 @@
 using Microsoft.AspNetCore.Identity;
+using System.ComponentModel.DataAnnotations;
 
 namespace NexusReader.Domain.Entities;
 
@@ -20,7 +21,9 @@ public class NexusUser : IdentityUser
     /// <summary>
     /// Unique identifier for the tenant (SaaS multi-tenancy support).
     /// </summary>
-    public Guid TenantId { get; set; }
+    [Required]
+    [MaxLength(128)]
+    public string TenantId { get; set; } = "global";
 
     /// <summary>
     /// Current subscription plan (e.g., "Free", "Pro", "Enterprise").

src/NexusReader.Infrastructure/DependencyInjection.cs

@@ -74,11 +74,13 @@ public static class DependencyInjection
 
         services.AddScoped<IAuthorizationHandler, ProUserHandler>();
 
-        services.AddMediatR(config => 
-        {
-            config.RegisterServicesFromAssembly(typeof(DependencyInjection).Assembly);
-        });
+        services.AddScoped<IInfrastructureMarker, InfrastructureMarker>();
 
         return services;
     }
+
+    public static System.Reflection.Assembly Assembly => typeof(DependencyInjection).Assembly;
 }
+
+public interface IInfrastructureMarker { }
+internal class InfrastructureMarker : IInfrastructureMarker { }

src/NexusReader.Infrastructure/Persistence/DbInitializer.cs

@@ -44,7 +44,7 @@ public static class DbInitializer
                     EmailConfirmed = true,
                     CurrentPlan = "Enterprise",
                     AITokenLimit = 1000000,
-                    TenantId = Guid.NewGuid()
+                    TenantId = Guid.NewGuid().ToString()
                 };
 
                 var createPowerUser = await userManager.CreateAsync(adminUser, "Admin123!");

src/NexusReader.Infrastructure/Services/KnowledgeService.cs

@@ -43,27 +43,27 @@ public class KnowledgeService : IKnowledgeService
         _tokenizer = TiktokenTokenizer.CreateForModel("gpt-4");
     }
 
-    public async Task<Result<KnowledgePacket>> GetKnowledgeAsync(string text, CancellationToken cancellationToken = default)
+    public async Task<Result<KnowledgePacket>> GetKnowledgeAsync(string text, string tenantId, CancellationToken cancellationToken = default)
     {
-        return await GetKnowledgeInternalAsync(text, PromptRegistry.KnowledgeExtractionSystemPrompt, "full", cancellationToken);
+        return await GetKnowledgeInternalAsync(text, tenantId, PromptRegistry.KnowledgeExtractionSystemPrompt, "full", cancellationToken);
     }
 
-    public async Task<Result<KnowledgePacket>> GetGraphDataAsync(string text, CancellationToken cancellationToken = default)
+    public async Task<Result<KnowledgePacket>> GetGraphDataAsync(string text, string tenantId, CancellationToken cancellationToken = default)
     {
-        return await GetKnowledgeInternalAsync(text, PromptRegistry.GraphExtractionPrompt, "graph", cancellationToken);
+        return await GetKnowledgeInternalAsync(text, tenantId, PromptRegistry.GraphExtractionPrompt, "graph", cancellationToken);
     }
 
-    public async Task<Result<KnowledgePacket>> GetSummaryAndQuizAsync(string text, CancellationToken cancellationToken = default)
+    public async Task<Result<KnowledgePacket>> GetSummaryAndQuizAsync(string text, string tenantId, CancellationToken cancellationToken = default)
     {
-        return await GetKnowledgeInternalAsync(text, PromptRegistry.SummaryAndQuizPrompt, "summary_quiz", cancellationToken);
+        return await GetKnowledgeInternalAsync(text, tenantId, PromptRegistry.SummaryAndQuizPrompt, "summary_quiz", cancellationToken);
     }
 
-    public async Task<Result<KnowledgePacket>> GetKnowledgeMapAsync(string text, CancellationToken cancellationToken = default)
+    public async Task<Result<KnowledgePacket>> GetKnowledgeMapAsync(string text, string tenantId, CancellationToken cancellationToken = default)
     {
-        return await GetKnowledgeInternalAsync(text, PromptRegistry.KM_ExtractionPrompt, "km_map", cancellationToken);
+        return await GetKnowledgeInternalAsync(text, tenantId, PromptRegistry.KM_ExtractionPrompt, "km_map", cancellationToken);
     }
 
-    private async Task<Result<KnowledgePacket>> GetKnowledgeInternalAsync(string text, string systemPrompt, string cacheSuffix, CancellationToken cancellationToken)
+    private async Task<Result<KnowledgePacket>> GetKnowledgeInternalAsync(string text, string tenantId, string systemPrompt, string cacheSuffix, CancellationToken cancellationToken)
     {
         if (string.IsNullOrWhiteSpace(text))
         {
@@ -84,7 +84,7 @@ public class KnowledgeService : IKnowledgeService
 
         // 1. Check Cache
         var cached = await _dbContext.SemanticKnowledgeCache
-            .FirstOrDefaultAsync(c => c.ContentHash == hash && c.PromptVersion == PromptVersion, cancellationToken);
+            .FirstOrDefaultAsync(c => c.ContentHash == hash && c.TenantId == tenantId && c.PromptVersion == PromptVersion, cancellationToken);
 
         if (cached != null)
         {
@@ -146,7 +146,7 @@ public class KnowledgeService : IKnowledgeService
                     OriginalText = normalizedText,
                     ModelId = _settings.Model,
                     PromptVersion = PromptVersion,
-                    TenantId = "global", // Default for shared cache, should be overridden by caller context if possible
+                    TenantId = tenantId,
                     Vector = vector,
                     CreatedAt = DateTime.UtcNow
                 };
@@ -163,7 +163,7 @@ public class KnowledgeService : IKnowledgeService
                 // 5. Process KM-RAG Units and Links if present
                 if (knowledgePacket.Units.Any())
                 {
-                    await ProcessKnowledgeUnitsAsync(knowledgePacket, "global", cancellationToken);
+                    await ProcessKnowledgeUnitsAsync(knowledgePacket, tenantId, cancellationToken);
                 }
 
                 await _dbContext.SaveChangesAsync(cancellationToken);
@@ -191,7 +191,7 @@ public class KnowledgeService : IKnowledgeService
             var unit = existing ?? new KnowledgeUnit { Id = unitId, TenantId = tenantId };
             unit.Type = Enum.TryParse<NexusReader.Domain.Enums.KnowledgeUnitType>(unitDto.Type, true, out var type) ? type : NexusReader.Domain.Enums.KnowledgeUnitType.Snippet;
             unit.Content = unitDto.Content;
-            unit.SourceId = "extracted"; // Should be passed from context
+            unit.SourceId = "extracted";
             unit.MetadataJson = JsonSerializer.Serialize(unitDto.Metadata);
 
             // Generate unit-specific embedding for granular retrieval
@@ -217,6 +217,44 @@ public class KnowledgeService : IKnowledgeService
         }
     }
 
+    public async Task<Result<GroundednessResult>> VerifyGroundednessAsync(string answer, string context, string tenantId, CancellationToken cancellationToken = default)
+    {
+        var systemPrompt = @"
+        You are a Fact-Checking AI. Evaluate if the 'Answer' is supported by the 'Context'.
+        Rate the groundedness from 0.0 to 1.0.
+        Return ONLY a JSON object: { ""score"": 0.9, ""rationale"": ""string"", ""isGrounded"": true }
+        ";
+
+        var userPrompt = $"Context: {context}\n\nAnswer: {answer}";
+
+        try
+        {
+            var options = new ChatOptions
+            {
+                Temperature = 0.0f, // Low temperature for factual checks
+                MaxOutputTokens = 500
+            };
+
+            var response = await _retryPipeline.ExecuteAsync(async ct => 
+                await _chatClient.GetResponseAsync(new List<ChatMessage>
+                {
+                    new ChatMessage(ChatRole.System, systemPrompt),
+                    new ChatMessage(ChatRole.User, userPrompt)
+                }, options, cancellationToken: ct), cancellationToken);
+
+            var rawJson = response.Text?.Trim() ?? "{}";
+            rawJson = rawJson.Replace("```json", "").Replace("```", "").Trim();
+            
+            var result = JsonSerializer.Deserialize<GroundednessResult>(rawJson, new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
+            
+            return result != null ? Result.Ok(result) : Result.Fail("Failed to parse groundedness result");
+        }
+        catch (Exception ex)
+        {
+            return Result.Fail(new Error("Failed to verify groundedness").CausedBy(ex));
+        }
+    }
+
     public async Task<Result<List<RelevantContext>>> GetRelevantContextAsync(string query, string tenantId, CancellationToken cancellationToken = default)
     {
         if (string.IsNullOrWhiteSpace(query)) return Result.Fail("Query is empty.");

src/NexusReader.Maui/MauiProgram.cs

@@ -49,6 +49,10 @@ public static class MauiProgram
 			builder.Services.AddScoped<IIdentityService, IdentityService>();
 			
 			builder.Services.AddApplication();
+			
+			builder.Services.AddMediatR(cfg => cfg.RegisterServicesFromAssemblies(
+				NexusReader.Application.DependencyInjection.Assembly
+			));
 
 			return builder.Build();
 		}

src/NexusReader.UI.Shared/Components/Molecules/GroundednessBadge.razor

@@ -1,7 +1,10 @@
 @using MediatR
 @using NexusReader.Application.Commands.AI
+@using NexusReader.Application.Abstractions.Services
 @using NexusReader.UI.Shared.Components.Atoms
+@using Microsoft.AspNetCore.Components.Authorization
 @inject IMediator Mediator
+@inject AuthenticationStateProvider AuthProvider
 
 <div class="groundedness-badge @GetStatusClass()" title="@_result?.Rationale">
     @if (_isChecking)
@@ -24,16 +27,29 @@
         border-radius: 12px;
         font-size: 0.75rem;
         font-weight: 600;
-        background: rgba(255,255,255,0.05);
-        border: 1px solid rgba(255,255,255,0.1);
+        background: rgba(255, 255, 255, 0.05);
+        border: 1px solid rgba(255, 255, 255, 0.1);
         transition: all 0.3s ease;
     }
 
-    .groundedness-badge.status-high { color: var(--nexus-neon); border-color: var(--nexus-neon); }
-    .groundedness-badge.status-medium { color: #ffaa00; border-color: #ffaa00; }
-    .groundedness-badge.status-low { color: #ff4444; border-color: #ff4444; }
+    .groundedness-badge.status-high {
+        color: var(--nexus-neon);
+        border-color: var(--nexus-neon);
+    }
 
-    .shimmer { opacity: 0.6; }
+    .groundedness-badge.status-medium {
+        color: #ffaa00;
+        border-color: #ffaa00;
+    }
+
+    .groundedness-badge.status-low {
+        color: #ff4444;
+        border-color: #ff4444;
+    }
+
+    .shimmer {
+        opacity: 0.6;
+    }
 </style>
 
 @code {
@@ -56,7 +72,10 @@
         _isChecking = true;
         StateHasChanged();
 
-        var res = await Mediator.Send(new VerifyGroundednessCommand(Answer, Context));
+        var authState = await AuthProvider.GetAuthenticationStateAsync();
+        var tenantId = authState.User.FindFirst("TenantId")?.Value ?? "global";
+
+        var res = await Mediator.Send(new VerifyGroundednessCommand(Answer, Context, tenantId));
         if (res.IsSuccess)
         {
             _result = res.Value;

src/NexusReader.UI.Shared/Services/KnowledgeCoordinator.cs

@@ -38,7 +38,7 @@ public sealed class KnowledgeCoordinator : IDisposable
         _interactionService.RequestHighlightBlock(nodeId);
     }
 
-    public async Task ProcessFullPageAsync(string fullContent)
+    public async Task ProcessFullPageAsync(string fullContent, string tenantId = "global")
     {
         if (string.IsNullOrWhiteSpace(fullContent)) return;
 
@@ -49,7 +49,7 @@ public sealed class KnowledgeCoordinator : IDisposable
         
         try
         {
-            var result = await _knowledgeService.GetGraphDataAsync(fullContent);
+            var result = await _knowledgeService.GetGraphDataAsync(fullContent, tenantId);
             if (result.IsSuccess)
             {
                 var packet = result.Value;
@@ -73,12 +73,12 @@ public sealed class KnowledgeCoordinator : IDisposable
         _graphService.SetActiveNode(blockId);
     }
 
-    public async Task<KnowledgePacket?> RequestSummaryAndQuizAsync(string content)
+    public async Task<KnowledgePacket?> RequestSummaryAndQuizAsync(string content, string tenantId = "global")
     {
         _quizService.SetHydrating(true);
         try
         {
-            var result = await _knowledgeService.GetSummaryAndQuizAsync(content);
+            var result = await _knowledgeService.GetSummaryAndQuizAsync(content, tenantId);
             if (result.IsSuccess)
             {
                 var packet = result.Value;

src/NexusReader.Web.Client/Services/WasmKnowledgeService.cs

@@ -14,22 +14,22 @@ public class WasmKnowledgeService : IKnowledgeService
         _httpClient = httpClient;
     }
 
-    public async Task<Result<KnowledgePacket>> GetKnowledgeAsync(string text, CancellationToken cancellationToken = default)
+    public async Task<Result<KnowledgePacket>> GetKnowledgeAsync(string text, string tenantId, CancellationToken cancellationToken = default)
     {
         return await CallKnowledgeApiAsync("/api/knowledge", text, cancellationToken);
     }
 
-    public async Task<Result<KnowledgePacket>> GetGraphDataAsync(string text, CancellationToken cancellationToken = default)
+    public async Task<Result<KnowledgePacket>> GetGraphDataAsync(string text, string tenantId, CancellationToken cancellationToken = default)
     {
         return await CallKnowledgeApiAsync("/api/knowledge/graph", text, cancellationToken);
     }
 
-    public async Task<Result<KnowledgePacket>> GetKnowledgeMapAsync(string text, CancellationToken cancellationToken = default)
+    public async Task<Result<KnowledgePacket>> GetKnowledgeMapAsync(string text, string tenantId, CancellationToken cancellationToken = default)
     {
         return await CallKnowledgeApiAsync("/api/knowledge/map", text, cancellationToken);
     }
 
-    public async Task<Result<KnowledgePacket>> GetSummaryAndQuizAsync(string text, CancellationToken cancellationToken = default)
+    public async Task<Result<KnowledgePacket>> GetSummaryAndQuizAsync(string text, string tenantId, CancellationToken cancellationToken = default)
     {
         return await CallKnowledgeApiAsync("/api/knowledge/summary", text, cancellationToken);
     }
@@ -53,6 +53,25 @@ public class WasmKnowledgeService : IKnowledgeService
             return Result.Fail(new Error($"Network error: {ex.Message}").CausedBy(ex));
         }
     }
+    public async Task<Result<GroundednessResult>> VerifyGroundednessAsync(string answer, string context, string tenantId, CancellationToken cancellationToken = default)
+    {
+        try
+        {
+            var response = await _httpClient.PostAsJsonAsync("/api/knowledge/verify-groundedness", new { answer, context, tenantId }, cancellationToken);
+            if (response.IsSuccessStatusCode)
+            {
+                var result = await response.Content.ReadFromJsonAsync<GroundednessResult>(cancellationToken: cancellationToken);
+                return result != null ? Result.Ok(result) : Result.Fail("Failed to deserialize groundedness result.");
+            }
+
+            var errorBody = await response.Content.ReadAsStringAsync(cancellationToken);
+            return Result.Fail($"Server error ({response.StatusCode}): {errorBody}");
+        }
+        catch (Exception ex)
+        {
+            return Result.Fail(new Error($"Network error: {ex.Message}").CausedBy(ex));
+        }
+    }
 
     private async Task<Result<KnowledgePacket>> CallKnowledgeApiAsync(string endpoint, string text, CancellationToken cancellationToken)
     {

src/NexusReader.Web.New/Program.cs

@@ -59,6 +59,11 @@ builder.Services.AddCascadingAuthenticationState();
 builder.Services.AddApplication();
 builder.Services.AddInfrastructure(builder.Configuration);
 
+builder.Services.AddMediatR(cfg => cfg.RegisterServicesFromAssemblies(
+    NexusReader.Application.DependencyInjection.Assembly,
+    NexusReader.Infrastructure.DependencyInjection.Assembly
+));
+
 // Authorization Policies
 builder.Services.AddScoped<IAuthorizationHandler, TokenLimitHandler>();
 builder.Services.AddAuthorizationBuilder()
@@ -114,6 +119,16 @@ builder.Services.Configure<IdentityOptions>(options =>
 
 var app = builder.Build();
 
+// Startup Validation
+using (var scope = app.Services.CreateScope())
+{
+    var marker = scope.ServiceProvider.GetService<IInfrastructureMarker>();
+    if (marker == null)
+    {
+        throw new InvalidOperationException("CRITICAL: Infrastructure layer was not registered. Ensure AddInfrastructure() is called in Program.cs.");
+    }
+}
+
 // Ensure Database is initialized and seeded
 using (var scope = app.Services.CreateScope())
 {
@@ -198,27 +213,40 @@ app.MapGet("/api/epub/{index}", async (int index, IEpubService epubService) =>
 
 var knowledgeApi = app.MapGroup("/api/knowledge").RequireAuthorization("HasAvailableTokens");
 
-knowledgeApi.MapPost("/", async (KnowledgeRequest request, IKnowledgeService knowledgeService) =>
+knowledgeApi.MapPost("/", async (KnowledgeRequest request, ClaimsPrincipal user, IKnowledgeService knowledgeService) =>
 {
-    var result = await knowledgeService.GetKnowledgeAsync(request.Text);
+    var tenantId = user.FindFirstValue("TenantId") ?? "global";
+    var result = await knowledgeService.GetKnowledgeAsync(request.Text, tenantId);
     if (result.IsSuccess) return Results.Ok(result.Value);
     return Results.BadRequest(result.Errors.Count > 0 ? result.Errors[0].Message : "Unknown server error");
 });
 
-knowledgeApi.MapPost("/graph", async (KnowledgeRequest request, IKnowledgeService knowledgeService) =>
+knowledgeApi.MapPost("/graph", async (KnowledgeRequest request, ClaimsPrincipal user, IKnowledgeService knowledgeService) =>
 {
-    var result = await knowledgeService.GetGraphDataAsync(request.Text);
+    var tenantId = user.FindFirstValue("TenantId") ?? "global";
+    var result = await knowledgeService.GetGraphDataAsync(request.Text, tenantId);
     if (result.IsSuccess) return Results.Ok(result.Value);
     return Results.BadRequest(result.Errors.Count > 0 ? result.Errors[0].Message : "Unknown server error");
 });
 
-knowledgeApi.MapPost("/summary", async (KnowledgeRequest request, IKnowledgeService knowledgeService) =>
+knowledgeApi.MapPost("/summary", async (KnowledgeRequest request, ClaimsPrincipal user, IKnowledgeService knowledgeService) =>
 {
-    var result = await knowledgeService.GetSummaryAndQuizAsync(request.Text);
+    var tenantId = user.FindFirstValue("TenantId") ?? "global";
+    var result = await knowledgeService.GetSummaryAndQuizAsync(request.Text, tenantId);
     if (result.IsSuccess) return Results.Ok(result.Value);
     return Results.BadRequest(result.Errors.Count > 0 ? result.Errors[0].Message : "Unknown server error");
 });
 
+knowledgeApi.MapPost("/verify-groundedness", async (GroundednessRequest request, ClaimsPrincipal user, IKnowledgeService knowledgeService) =>
+{
+    var tenantId = user.FindFirstValue("TenantId") ?? "global";
+    var result = await knowledgeService.VerifyGroundednessAsync(request.Answer, request.Context, tenantId);
+    if (result.IsSuccess) return Results.Ok(result.Value);
+    return Results.BadRequest(result.Errors.Count > 0 ? result.Errors[0].Message : "Unknown server error");
+});
+
+
+
 knowledgeApi.MapDelete("/", async (IKnowledgeService knowledgeService) =>
 {
     var result = await knowledgeService.ClearCacheAsync();
@@ -377,3 +405,4 @@ app.MapRazorComponents<App>()
 app.Run();
 
 public record KnowledgeRequest(string Text);
+public record GroundednessRequest(string Answer, string Context);