fix(audio,flutter): parse Android UsbHeadset and Hdmi route strings

apps/chanora_flutter/lib/services/audio_lifecycle_service.dart: extend parseBridgeAudioRoute to handle 'UsbHeadset' (maps to wiredHeadset — USB audio is functionally a wired-class device, matching AndroidAudioLifecycleController.classifyCurrentRoute's own preference ordering at line 176) and 'Hdmi' (maps to unknown — HDMI is a display-out transport, not a voice-call audio path; no existing BridgeAudioRoute variant fits; safer to leave as unknown than to misclassify as Speaker). Previously these Android-emitted strings hit the default branch and silently became BridgeAudioRoute.unknown.

apps/chanora_flutter/test/services/audio_lifecycle_service_test.dart: split the existing single test into three — iOS-classified strings (preserved), Android UsbHeadset (new), Android Hdmi (new). flutter test: 3 passed, 0 failed.

apps/chanora_flutter/lib/services/audio_lifecycle_service.dart

@@ -14,11 +14,15 @@ rust.BridgeAudioRoute parseBridgeAudioRoute(String value) {
     case 'Speaker':
       return rust.BridgeAudioRoute.speaker;
     case 'WiredHeadset':
+    case 'UsbHeadset':
       return rust.BridgeAudioRoute.wiredHeadset;
     case 'BluetoothHfp':
       return rust.BridgeAudioRoute.bluetoothHfp;
     case 'BluetoothA2dp':
       return rust.BridgeAudioRoute.bluetoothA2Dp;
+    case 'Hdmi':
+    case 'Unknown':
+      return rust.BridgeAudioRoute.unknown;
     default:
       return rust.BridgeAudioRoute.unknown;
   }

apps/chanora_flutter/test/services/audio_lifecycle_service_test.dart

@@ -4,7 +4,7 @@ import 'package:chanora_flutter/services/audio_lifecycle_service.dart';
 import 'package:chanora_flutter/src/rust/api.dart' as rust;
 
 void main() {
-  test('parseBridgeAudioRoute maps platform route names', () {
+  test('parseBridgeAudioRoute maps iOS-classified route strings', () {
     expect(parseBridgeAudioRoute('Earpiece'), rust.BridgeAudioRoute.earpiece);
     expect(parseBridgeAudioRoute('Speaker'), rust.BridgeAudioRoute.speaker);
     expect(
@@ -22,4 +22,22 @@ void main() {
     expect(parseBridgeAudioRoute('Unknown'), rust.BridgeAudioRoute.unknown);
     expect(parseBridgeAudioRoute('Other'), rust.BridgeAudioRoute.unknown);
   });
+
+  test('parseBridgeAudioRoute maps Android UsbHeadset to wiredHeadset', () {
+    // AndroidAudioLifecycleController.classifyDevice emits 'UsbHeadset' for
+    // AudioDeviceInfo.TYPE_USB_HEADSET. USB audio is functionally a
+    // wired-class device — the Kotlin classifier's own preference ordering
+    // (line 176 of AndroidAudioLifecycleController.kt) groups it with
+    // WiredHeadset/BluetoothHfp/BluetoothA2dp.
+    expect(parseBridgeAudioRoute('UsbHeadset'),
+        rust.BridgeAudioRoute.wiredHeadset);
+  });
+
+  test('parseBridgeAudioRoute maps Android Hdmi to unknown', () {
+    // HDMI is a display-out transport, not a voice-call audio path; no
+    // existing BridgeAudioRoute variant fits. Treat as unknown rather
+    // than misclassify as Speaker.
+    expect(parseBridgeAudioRoute('Hdmi'), rust.BridgeAudioRoute.unknown);
+  });
 }
+