feat(intelligence): implement Global AI Q&A screen and paywall blocker

- Implemented standard empty and active chat conversation states for the `/intelligence` page
- Created interactive `AiResponseRenderer` with AOT-compliant sentence splitting and payment gateway simulation
- Added scoped `LibraryStateService` to synchronize book ownership and updates across the application
- Obfuscated paywalled content in DOM to prevent inspection bypass
- Fixed local port connection mismatch by updating API configurations to use port 5104

src/NexusReader.Web.Client/Program.cs

@@ -27,6 +27,7 @@ builder.Services.AddScoped<IReaderNavigationService, ReaderNavigationService>();
 builder.Services.AddScoped<IKnowledgeGraphService, KnowledgeGraphService>();
 builder.Services.AddScoped<IReaderInteractionService, ReaderInteractionService>();
 builder.Services.AddScoped<IReaderStateService, ReaderStateService>();
+builder.Services.AddScoped<ILibraryStateService, LibraryStateService>();
 builder.Services.AddScoped<KnowledgeCoordinator>();
 builder.Services.AddScoped<ISyncService, SyncService>();