[windows] Desktop notifications never reach Windows; in-app banner misattributes to system settings.

[MichaelRogueAndWolf]

[windows] Desktop notifications never reach Windows; in-app banner misattributes to system settings. On Windows 11, the app shows "Desktop notifications are blocked. Enable them in your system settings" — but Buzz never appears in Settings → Notifications' app list, and HKCU...\Notifications\Settings contains no xyz.block.buzz.app entry, i.e. no toast was ever registered. The WebView2 profile's notification permission map is empty (not denied); even with an explicit "setting":1 grant for http://tauri.localhost:80,* in the profile Preferences, no toast is raised. Start Menu shortcut exists with correct AUMID (xyz.block.buzz.app); toast master switch enabled. Looks like the WebView2 NotificationReceived → Windows toast bridge is unimplemented on Windows, and the banner should say "not supported yet" rather than pointing users at system settings.

[MrGrasss]

Still reproduces on Windows 11 with Buzz Desktop 0.5.8 (latest), same signature:

• Settings -> Notifications shows "Desktop notifications are blocked" and the Desktop alerts toggle is disabled.
• Windows side is clean: global notifications on, Do Not Disturb off, no NoToastApplicationNotification policy in HKCU or HKLM.
• No xyz.block.buzz.app entry under HKCU\Software\Microsoft\Windows\CurrentVersion\Notifications\Settings (never registered).
• WebView2 profile has no notification content-setting entry for the app either (empty map, not denied).
• Start Menu shortcut is present, targeting the installed exe.

So nothing is actually denied at the OS or WebView2 layer. The app reports "blocked" for a state that is really "never requested/registered", and the disabled in-app toggle leaves no way to trigger the request. Confirming this is not fixed as of 0.5.8.

[ranjank2alpha]

Submitted a complete implementation for native Windows WinRT Toast Notifications in #6876.

Key details:

• Native WinRT Toast Delivery: Wires native toast dispatch via auri-winrt-notification and COM bindings.
• AUMID & Process MTA: Fixes the missing registry/app registration by initializing process-wide MTA and setting PKEY_AppUserModel_ID on the Start Menu shortcut, allowing Windows to route and display toasts in the Action Center.
• Direct Permission Verification: Bypasses the WebView2 startup permission latch by verifying against the backend on Windows.

Ready for review with clean DCO and full test coverage in #6876.