feat: implement dynamic knowledge graph updates and state management services

src/NexusReader.UI.Shared/Components/Organisms/KnowledgeGraph.razor

@@ -6,6 +6,7 @@
 @inject IMediator Mediator
 @inject IJSRuntime JS
 @inject IFocusModeService FocusMode
+@inject IKnowledgeGraphService GraphService
 
 <div class="knowledge-graph-container" id="@ContainerId">
     @if (GraphData == null)
@@ -37,6 +38,21 @@
     protected override void OnInitialized()
     {
         FocusMode.OnFocusModeChanged += HandleFocusSimulation;
+        GraphService.OnGraphUpdated += HandleGraphUpdate;
+        GraphService.OnActiveNodeChanged += HandleActiveNodeChange;
+    }
+
+    private async void HandleGraphUpdate()
+    {
+        if (_module == null) return;
+        await _module.InvokeVoidAsync("updateData", GraphService.CurrentGraphData);
+        await InvokeAsync(StateHasChanged);
+    }
+
+    private async void HandleActiveNodeChange(string nodeId)
+    {
+        if (_module == null) return;
+        await _module.InvokeVoidAsync("setActiveNode", nodeId);
     }
 
     protected override async Task OnAfterRenderAsync(bool firstRender)