feat: Android Oboe voice backend — WebRTC APM, VAD, HW/SW toggle, BBCode welcome, link trust, foreground task

Audio engine (Rust):
- Android Oboe: WebRTC APM (AEC/NS/AGC/HPF) + TEN/Silero ONNX VAD
- Hardware effects (JNI) with software fallback per-effect
- Render reference buffer for AEC between output/capture callbacks
- Voice activity gate: suppress transmission when speaker muted (all platforms)
- Audio focus (SDD-109) + Bluetooth SCO (SDD-110) via JNI
- ONNX Runtime 1.26 via ort 2.0.0-rc.12 (down from rc.10, ndarray 0.17)
- VAD worker channel capacity 8→32, initial seq u64::MAX (warm-up fix)
- TEN VAD default backend (was Silero)
- Platform→WebrtcApm resolution after hardware binding
- oboe-rs edisonjwa fork with get_raw_session_id()

Android Kotlin:
- AndroidAudioFocusController + AndroidBluetoothScoController
- AndroidAudioLifecycleController (route changes to Flutter)
- ProGuard rules for new controllers

Flutter UI:
- VoiceSettings: Android HW/SW toggle (Platform auto / WebRTC APM)
- VoiceStatusChip: mute warning border + Speaker muted label
- BBCode welcome message parser (BbCodeText, case-insensitive)
- Welcome message foldable (expanded by default)
- Link trust dialog (domain wildcards, SharedPreferences)
- HapticFeedback on voice sheet opener
- Server name in AppBar, version v0.1.0
- Default channel (id=1) visible, serverquery clients hidden
- flutter_foreground_task integration

Config:
- ort load-dynamic on all non-iOS (Android/Linux/Windows)
- ONNX Runtime AAR 1.26.0
- ndarray moved to common deps (was Apple-only)

apps/chanora_flutter/pubspec.lock

@@ -246,6 +246,14 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  flutter_foreground_task:
+    dependency: "direct main"
+    description:
+      name: flutter_foreground_task
+      sha256: fc5c01a5e1b8f7bb51d0c737714f0c50440dbdf1aeddc5f8cbba313aa6fd4856
+      url: "https://pub.dev"
+    source: hosted
+    version: "9.2.2"
   flutter_lints:
     dependency: "direct dev"
     description:
@@ -629,6 +637,62 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "0.28.0"
+  shared_preferences:
+    dependency: "direct main"
+    description:
+      name: shared_preferences
+      sha256: c3025c5534b01739267eb7d76959bbc25a6d10f6988e1c2a3036940133dd10bf
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.5"
+  shared_preferences_android:
+    dependency: transitive
+    description:
+      name: shared_preferences_android
+      sha256: e8d4762b1e2e8578fc4d0fd548cebf24afd24f49719c08974df92834565e2c53
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.23"
+  shared_preferences_foundation:
+    dependency: transitive
+    description:
+      name: shared_preferences_foundation
+      sha256: "4e7eaffc2b17ba398759f1151415869a34771ba11ebbccd1b0145472a619a64f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.6"
+  shared_preferences_linux:
+    dependency: transitive
+    description:
+      name: shared_preferences_linux
+      sha256: "580abfd40f415611503cae30adf626e6656dfb2f0cee8f465ece7b6defb40f2f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
+  shared_preferences_platform_interface:
+    dependency: transitive
+    description:
+      name: shared_preferences_platform_interface
+      sha256: "649dc798a33931919ea356c4305c2d1f81619ea6e92244070b520187b5140ef9"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.2"
+  shared_preferences_web:
+    dependency: transitive
+    description:
+      name: shared_preferences_web
+      sha256: c49bd060261c9a3f0ff445892695d6212ff603ef3115edbb448509d407600019
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.3"
+  shared_preferences_windows:
+    dependency: transitive
+    description:
+      name: shared_preferences_windows
+      sha256: "94ef0f72b2d71bc3e700e025db3710911bd51a71cefb65cc609dd0d9a982e3c1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
   shelf:
     dependency: transitive
     description:
@@ -722,6 +786,70 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.4.0"
+  url_launcher:
+    dependency: "direct main"
+    description:
+      name: url_launcher
+      sha256: f6a7e5c4835bb4e3026a04793a4199ca2d14c739ec378fdfe23fc8075d0439f8
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.2"
+  url_launcher_android:
+    dependency: transitive
+    description:
+      name: url_launcher_android
+      sha256: "17bc677f0b301615530dd1d67e0a9828cafa2d0b6b6eae4cd3679b7eac4a273c"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.3.30"
+  url_launcher_ios:
+    dependency: transitive
+    description:
+      name: url_launcher_ios
+      sha256: "580fe5dfb51671ae38191d316e027f6b76272b026370708c2d898799750a02b0"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.4.1"
+  url_launcher_linux:
+    dependency: transitive
+    description:
+      name: url_launcher_linux
+      sha256: d5e14138b3bc193a0f63c10a53c94b91d399df0512b1f29b94a043db7482384a
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.2.2"
+  url_launcher_macos:
+    dependency: transitive
+    description:
+      name: url_launcher_macos
+      sha256: "368adf46f71ad3c21b8f06614adb38346f193f3a59ba8fe9a2fd74133070ba18"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.2.5"
+  url_launcher_platform_interface:
+    dependency: transitive
+    description:
+      name: url_launcher_platform_interface
+      sha256: "552f8a1e663569be95a8190206a38187b531910283c3e982193e4f2733f01029"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.2"
+  url_launcher_web:
+    dependency: transitive
+    description:
+      name: url_launcher_web
+      sha256: "85c81589622fbc87c1c683aaea164d3604a7777495a79d91e39ffcdec39ddb34"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.3"
+  url_launcher_windows:
+    dependency: transitive
+    description:
+      name: url_launcher_windows
+      sha256: "712c70ab1b99744ff066053cbe3e80c73332b38d46e5e945c98689b2e66fc15f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.5"
   vector_math:
     dependency: transitive
     description: