Initial commit: NexusArchitect Professional Workstation Overhaul

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

@@ -0,0 +1,13 @@
+namespace NexusReader.UI.Shared.Services;
+
+public sealed class ThemeService : IThemeService
+{
+    public bool IsLightMode { get; private set; } = false;
+    public event Action? OnThemeChanged;
+
+    public void ToggleTheme()
+    {
+        IsLightMode = !IsLightMode;
+        OnThemeChanged?.Invoke();
+    }
+}