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/components/ScreenShareViewer.tsx

@@ -95,6 +95,13 @@ export function ScreenShareViewer({
           autoPlay
           playsInline
           muted
+          // Suppress the browser's built-in <video> context menu
+          // ("Save Video As…", PiP, …) so the right-click event bubbles
+          // to the wrapping tile div in InCallPanel — that's where the
+          // app's volume / mute menu is wired up. Without this, the
+          // native menu opens on top of ours in focus + fullscreen
+          // modes (where the video covers the whole tile).
+          onContextMenu={(e) => e.preventDefault()}
           onDoubleClick={toggleFullscreen}
           className="block h-full w-full flex-1 cursor-zoom-in bg-black object-contain"
         />