perf: optimize app startup and background lifecycles

electron/main/window-material.ts

@@ -12,12 +12,13 @@ type NativeWindowMaterialOptions = Pick<
 export function getNativeWindowMaterialOptions(
   platform: NodeJS.Platform,
 ): NativeWindowMaterialOptions {
-  if (platform !== 'darwin') return {};
-
+  // Keep every platform on the same opaque surface. Native vibrancy forces
+  // transparent compositing and makes every backdrop-filter pay the cost of
+  // sampling the window behind it. Makelore's light palette already provides
+  // the visual hierarchy without a native material layer.
   return {
-    backgroundColor: '#00000000',
-    transparent: true,
-    vibrancy: 'under-window',
-    visualEffectState: 'active',
+    backgroundColor: '#FFFFFF',
+    transparent: false,
+    ...(platform === 'darwin' ? { visualEffectState: 'inactive' as const } : {}),
   };
 }