refactor(tauri-bridge): split TauriEventBridge into per-concern hooks (#682)

Each Rust<->React bridge concern moves into its own hook under
hooks/tauriBridge/; TauriEventBridge just composes them:

- useZipDownloadBridge        download:zip:progress
- usePreviewBridge            audio:preview-* lifecycle
- useAudioDeviceBridge        audio:device-changed / -reset
- useCliBridge                full cli:* listener surface
- useTrayIconSync             tray-icon visibility
- useInAppKeybindings         configurable keydown chords
- useMediaAndWindowBridge     media keys, tray, shortcuts, close/force-quit
- usePlayerSnapshotPublisher  psysonic --info JSON snapshot

Pure code-move — event names, payloads, effect deps and cleanup all
verbatim. The MainApp call site is unchanged.

src/hooks/tauriBridge/usePreviewBridge.ts

@@ -0,0 +1,21 @@
+import { useEffect } from 'react';
+import { listen } from '@tauri-apps/api/event';
+import { usePreviewStore } from '../../store/previewStore';
+
+/** Track-preview lifecycle: Rust audio engine emits start/progress/end. The
+ * store mirrors them so any tracklist row can render its preview UI. */
+export function usePreviewBridge() {
+  useEffect(() => {
+    const unlistenFns: Array<() => void> = [];
+    listen<string>('audio:preview-start', e => {
+      usePreviewStore.getState()._onStart(e.payload);
+    }).then(u => unlistenFns.push(u));
+    listen<{ id: string; elapsed: number; duration: number }>('audio:preview-progress', e => {
+      usePreviewStore.getState()._onProgress(e.payload.id, e.payload.elapsed, e.payload.duration);
+    }).then(u => unlistenFns.push(u));
+    listen<{ id: string; reason: string }>('audio:preview-end', e => {
+      usePreviewStore.getState()._onEnd(e.payload.id);
+    }).then(u => unlistenFns.push(u));
+    return () => { unlistenFns.forEach(fn => fn()); };
+  }, []);
+}