Initial commit: NexusArchitect Professional Workstation Overhaul

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

@@ -0,0 +1,44 @@
+using Microsoft.JSInterop;
+
+namespace NexusReader.UI.Shared.Services;
+
+public sealed class FocusModeService : IFocusModeService
+{
+    private readonly IJSRuntime _jsRuntime;
+    public bool IsFocusModeActive { get; private set; }
+    public event Action? OnFocusModeChanged;
+
+    public FocusModeService(IJSRuntime jsRuntime)
+    {
+        _jsRuntime = jsRuntime;
+    }
+
+    public async Task InitializeAsync()
+    {
+        try
+        {
+            var value = await _jsRuntime.InvokeAsync<string>("localStorage.getItem", "nexus_focus_mode");
+            if (value == "true" && !IsFocusModeActive)
+            {
+                IsFocusModeActive = true;
+                OnFocusModeChanged?.Invoke();
+            }
+        }
+        catch
+        {
+            // Ignored during pre-rendering or unsupported environments
+        }
+    }
+
+    public async Task ToggleAsync()
+    {
+        IsFocusModeActive = !IsFocusModeActive;
+        OnFocusModeChanged?.Invoke();
+
+        try
+        {
+            await _jsRuntime.InvokeVoidAsync("localStorage.setItem", "nexus_focus_mode", IsFocusModeActive ? "true" : "false");
+        }
+        catch { }
+    }
+}