feat(desktop): port v0.11.4-v0.15.2 from Tauri to Electron + Discord-parity audio (v0.16.0)

Chronological port of every Tauri release commit (v0.11.4 -> v0.15.2)
into the Electron rebuild, plus Discord-style audio handling that goes
beyond the Tauri original.

Highlights:
  - All 17 Tauri release commits ported (audio fixes, custom notification
    sound, Discord-style chat UX, profile banner, changelog page,
    Discord-parity call UX, screen-share echo + re-watch UX, audio-loop
    fix).
  - Native napi-rs audio-loopback addon with WASAPI process-loopback:
      * EXCLUDE_TARGET_PROCESS_TREE for full-screen shares -> peers
        never hear themselves echoed back through the capture.
      * INCLUDE_TARGET_PROCESS_TREE for window shares -> only the
        picked window's audio is captured, not the whole OS mixer
        (Discord parity).
      * HWND -> PID resolution via Win32 GetWindowThreadProcessId.
  - Discord-style screen-source picker (thumbnail grid, screens vs
    apps tabs, live-refreshing thumbnails).
  - Hash routing fix for packaged builds (file:// can't resolve
    BrowserRouter paths).
  - Tauri sources removed (apps/desktop/src-tauri).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/desktop/src/lib/osNotify.ts

@@ -1,29 +1,17 @@
-import {
-  isPermissionGranted,
-  requestPermission,
-  sendNotification,
-} from '@tauri-apps/plugin-notification';
+// OS notifications via the Electron preload bridge. The exported API
+// stays identical to the Tauri-era version so callers don't change.
+//
+// Permission under Electron is implicit ('granted' always). The legacy
+// ASKED marker in localStorage is kept so we don't re-prompt after a
+// previously-denied run; we just fast-succeed now.
 
 import { isTauriRuntime } from './globalShortcut';
 
-// Tracks whether permission has already been requested this session so we
-// don't spam the OS prompt. Actual permission state lives in the OS, but we
-// also persist a "we've asked" marker in localStorage so reloads don't
-// re-request (OS would block anyway after denial, but calling it every reload
-// triggers noisy plugin warnings on some platforms).
 let permissionChecked = false;
 let permissionGranted = false;
 
 const ASKED_KEY = 'chatapp.notif.asked';
 
-function readAskedMarker(): boolean {
-  try {
-    return window.localStorage.getItem(ASKED_KEY) === '1';
-  } catch {
-    return false;
-  }
-}
-
 function writeAskedMarker(): void {
   try {
     window.localStorage.setItem(ASKED_KEY, '1');
@@ -36,21 +24,13 @@ export async function ensureNotificationPermission(): Promise<boolean> {
   if (permissionChecked) return permissionGranted;
   permissionChecked = true;
   if (!isTauriRuntime()) {
-    // Web preview / Chrome — Tauri notification plugin not available.
     permissionGranted = false;
     return false;
   }
   try {
-    let granted = await isPermissionGranted();
-    if (!granted && !readAskedMarker()) {
-      // First-install: prompt the user once. After this we remember via the
-      // marker and never re-prompt — the user can re-enable later via OS
-      // system settings if they change their mind.
-      const result = await requestPermission();
-      granted = result === 'granted';
-      writeAskedMarker();
-    }
-    permissionGranted = granted;
+    const state = await window.electronAPI.getNotificationPermission();
+    permissionGranted = state === 'granted';
+    writeAskedMarker();
   } catch (err: unknown) {
     permissionGranted = false;
     console.warn('notification permission check failed', err);
@@ -65,7 +45,7 @@ export function isAppFocused(): boolean {
 interface NotifyOpts {
   title: string;
   body?: string;
-  // Force notification even when app is focused. Default: suppress if focused.
+  /** Force notification even when app is focused. Default: suppress if focused. */
   force?: boolean;
 }
 
@@ -75,8 +55,12 @@ export async function notify({ title, body, force = false }: NotifyOpts): Promis
   const granted = await ensureNotificationPermission();
   if (!granted) return;
   try {
-    sendNotification({ title, ...(body ? { body } : {}) });
+    await window.electronAPI.notify({
+      title,
+      body: body ?? '',
+      silent: true,
+    });
   } catch (err: unknown) {
-    console.error('sendNotification failed', err);
+    console.error('notify failed', err);
   }
 }