fix: Notification audio

toju-app/src/app/domains/notifications/README.md

@@ -203,6 +203,7 @@ Additional runtime guards:
 The Electron main process handles the actual desktop notification and window-attention behavior.
 
 - `show-desktop-notification` creates a system `Notification` with the window icon when supported.
+- `show-desktop-notification` skips the OS toast while the main window is visible and maximized.
 - Notification clicks restore, show, and focus the main window.
 - `request-window-attention` flashes the taskbar entry directly when Electron is minimized or otherwise backgrounded and actionable unread exists.
 - `show-desktop-notification` can still request attention for live toast delivery.
@@ -210,7 +211,7 @@ The Electron main process handles the actual desktop notification and window-att
 
 ### Platform-specific policy
 
-- Windows: the facade also plays `AppSound.Notification` before showing the desktop notification.
+- Windows: the facade only plays `AppSound.Notification` when the app is not the active selected window.
 - Linux: desktop alerts are expected to surface through the system notification center, with window attention requested when the app is backgrounded.
 - macOS and browser-only builds use the same desktop notification adapter, but there is no extra renderer-side sound policy in this domain.