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)

crates/chanora_audio/src/audio_processing.rs

@@ -58,7 +58,7 @@ impl AudioRoute {
 pub enum IosVoiceProcessingMode {
     /// Shipping default: Apple VoiceProcessingIO owns AEC/NS/AGC.
     PlatformVoiceProcessing,
-    /// Experimental Sonora capture-processing path.
+    /// Experimental raw capture-processing path.
     SonoraExperimental,
 }
 
@@ -69,7 +69,7 @@ pub enum AudioBackend {
     PlatformVoiceProcessing,
     /// Rust-native Sonora backend.
     Sonora,
-    /// Future WebRTC APM backend.
+    /// WebRTC Audio Processing Module backend.
     WebrtcApm,
     /// No processing.
     Noop,
@@ -168,9 +168,9 @@ impl Default for AudioProcessingConfig {
             route: AudioRoute::Speaker,
             ios_mode: IosVoiceProcessingMode::PlatformVoiceProcessing,
             processing_backend: AudioBackend::PlatformVoiceProcessing,
-            vad_backend: VadBackend::SileroOnnx,
+            vad_backend: VadBackend::TenVad,
             aec: EffectOwner::Platform,
-            // iOS VPIO owns NS/AGC on the default shipping path. Rust/Sonora
+            // iOS VPIO owns NS/AGC on the default shipping path. Software
             // effects are opt-in through the experimental raw route only.
             ns: EffectOwner::Platform,
             agc: EffectOwner::Platform,
@@ -194,19 +194,23 @@ impl AudioProcessingConfig {
         }
         if self.ios_mode == IosVoiceProcessingMode::PlatformVoiceProcessing
             && (self.processing_backend == AudioBackend::Sonora
+                || self.processing_backend == AudioBackend::WebrtcApm
                 || self.aec == EffectOwner::Sonora
+                || self.aec == EffectOwner::WebrtcApm
                 || self.ns == EffectOwner::Sonora
-                || self.agc == EffectOwner::Sonora)
+                || self.ns == EffectOwner::WebrtcApm
+                || self.agc == EffectOwner::Sonora
+                || self.agc == EffectOwner::WebrtcApm)
         {
             return Err(AudioError::InvalidAudioProcessingConfig(
-                "Sonora cannot be enabled with iOS VoiceProcessingIO".to_string(),
+                "software audio processing cannot be enabled with iOS VoiceProcessingIO"
+                    .to_string(),
             ));
         }
         if self.ios_mode == IosVoiceProcessingMode::SonoraExperimental {
-            if self.processing_backend != AudioBackend::Sonora {
+            if self.processing_backend != AudioBackend::WebrtcApm {
                 return Err(AudioError::InvalidAudioProcessingConfig(
-                    "ios Sonora experimental mode requires the Sonora processing backend"
-                        .to_string(),
+                    "ios raw processing mode requires the WebRTC APM backend".to_string(),
                 ));
             }
         }
@@ -246,9 +250,9 @@ mod tests {
     }
 
     #[test]
-    fn platform_voice_processing_rejects_sonora_effects() {
+    fn platform_voice_processing_rejects_software_effects() {
         let config = AudioProcessingConfig {
-            ns: EffectOwner::Sonora,
+            ns: EffectOwner::WebrtcApm,
             ..AudioProcessingConfig::default()
         };
 
@@ -261,13 +265,13 @@ mod tests {
     }
 
     #[test]
-    fn sonora_experimental_allows_full_sonora_chain() {
+    fn raw_processing_allows_full_webrtc_apm_chain() {
         let config = AudioProcessingConfig {
             ios_mode: IosVoiceProcessingMode::SonoraExperimental,
-            processing_backend: AudioBackend::Sonora,
-            aec: EffectOwner::Sonora,
-            ns: EffectOwner::Sonora,
-            agc: EffectOwner::Sonora,
+            processing_backend: AudioBackend::WebrtcApm,
+            aec: EffectOwner::WebrtcApm,
+            ns: EffectOwner::WebrtcApm,
+            agc: EffectOwner::WebrtcApm,
             ..AudioProcessingConfig::default()
         };
 
@@ -275,13 +279,13 @@ mod tests {
     }
 
     #[test]
-    fn sonora_experimental_rejects_non_sonora_backend() {
+    fn raw_processing_rejects_non_webrtc_apm_backend() {
         let config = AudioProcessingConfig {
             ios_mode: IosVoiceProcessingMode::SonoraExperimental,
             processing_backend: AudioBackend::PlatformVoiceProcessing,
-            aec: EffectOwner::Sonora,
-            ns: EffectOwner::Sonora,
-            agc: EffectOwner::Sonora,
+            aec: EffectOwner::WebrtcApm,
+            ns: EffectOwner::WebrtcApm,
+            agc: EffectOwner::WebrtcApm,
             ..AudioProcessingConfig::default()
         };