fix(desktop): honor vibrancy toggle for window transparency

Tie macOS window transparency to the vibrancy setting so disabling vibrancy actually removes transparent backgrounds. Clarify settings copy that full transparency changes take effect for new windows or after restart.

packages/desktop/src-tauri/src/main.rs

@@ -2573,7 +2573,7 @@ fn apply_platform_window_config<M: Manager<tauri::Wry>>(
 ) -> WebviewWindowBuilder<'_, tauri::Wry, M> {
     #[cfg(target_os = "macos")]
     let builder = builder
-        .transparent(true)
+        .transparent(read_desktop_vibrancy_enabled())
         .hidden_title(true)
         .title_bar_style(tauri::TitleBarStyle::Overlay)
         .traffic_light_position(tauri::Position::Logical(tauri::LogicalPosition {

packages/ui/src/components/sections/openchamber/OpenChamberVisualSettings.tsx

@@ -538,7 +538,7 @@ export const OpenChamberVisualSettings: React.FC<OpenChamberVisualSettingsProps>
                                             Window vibrancy
                                         </span>
                                         <span className="typography-meta text-muted-foreground">
-                                            Translucent window background. Disabling may reduce energy usage.
+                                            Translucent window background. Disabling may reduce energy usage. Existing windows update immediately, but full transparency changes apply to new windows or after restart.
                                         </span>
                                     </div>
                                 </div>