Merge pull request 'Release v26.04.15.1 — Dynamic voice silence threshold' (#24) from dev into main

The previous -40 dBFS static threshold sat right on top of typical
phone mic ambient, so silence detection rarely fired and the user
always had to tap stop manually.

Silence threshold is now dynamic: track the session peak dBFS and
treat "silent" as 15 dB below peak. Auto-calibrates per mic and
environment rather than assuming a fixed ambient level.

- Grace period (1500 ms) at start so the user has time to begin
  speaking before checks arm.
- Static -35 dB fallback until the peak clears -20 dB so a dead-
  silent session doesn't spin forever.
- Silence duration bumped 1500 → 2000 ms for breathing room.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/app.dart

@@ -653,6 +653,7 @@ class _QuickCaptureBarState extends ConsumerState<_QuickCaptureBar> {
                 VoiceMicButton(
                   mode: ref.watch(voiceProvider).mode,
                   voiceModeActive: ref.watch(voiceProvider).voiceModeActive,
+                  amplitude: ref.watch(voiceProvider).amplitude,
                   onTap: _toggleCaptureMic,
                 ),
                 IconButton(

lib/providers/voice_provider.dart

@@ -59,22 +59,29 @@ class VoiceState {
   final VoiceMode mode;
   final bool voiceModeActive;
   final bool available;
+  /// Normalized mic amplitude 0.0–1.0 while recording. Drives the live
+  /// pulse on VoiceMicButton so the user has obvious feedback that audio
+  /// is actually being picked up.
+  final double amplitude;
 
   const VoiceState({
     this.mode = VoiceMode.idle,
     this.voiceModeActive = false,
     this.available = true,
+    this.amplitude = 0.0,
   });
 
   VoiceState copyWith({
     VoiceMode? mode,
     bool? voiceModeActive,
     bool? available,
+    double? amplitude,
   }) =>
       VoiceState(
         mode: mode ?? this.mode,
         voiceModeActive: voiceModeActive ?? this.voiceModeActive,
         available: available ?? this.available,
+        amplitude: amplitude ?? this.amplitude,
       );
 }
 
@@ -92,10 +99,23 @@ class VoiceNotifier extends Notifier<VoiceState> {
   StreamSubscription<Amplitude>? _amplitudeSubscription;
 
   // Recording / silence detection
+  //
+  // Silence threshold is dynamic: we track the session peak dBFS and treat
+  // "silent" as "current level is at least _dropFromPeakDb below peak."
+  // This auto-calibrates to whatever mic + room the user is on rather than
+  // assuming a fixed ambient level. Until the peak climbs above
+  // _dynamicArmDb we fall back to a conservative static threshold so a
+  // quiet room doesn't spin forever. A grace period at the start of the
+  // recording gives the user time to begin speaking before silence checks
+  // arm.
   int _recordingStartMs = 0;
   int _silenceMs = 0;
-  static const _silenceThresholdDb = -40.0;
-  static const _silenceDurationMs = 1500;
+  double _peakDb = -100.0;
+  static const _fallbackThresholdDb = -35.0;
+  static const _dropFromPeakDb = 15.0;
+  static const _dynamicArmDb = -20.0;
+  static const _graceMs = 1500;
+  static const _silenceDurationMs = 2000;
   static const _minRecordingMs = 300;
 
   // Voice mode callbacks
@@ -229,6 +249,7 @@ class VoiceNotifier extends Notifier<VoiceState> {
     if (!state.voiceModeActive) return;
 
     _silenceMs = 0;
+    _peakDb = -100.0;
     _recordingStartMs = DateTime.now().millisecondsSinceEpoch;
     state = state.copyWith(mode: VoiceMode.recording);
 
@@ -267,14 +288,33 @@ class VoiceNotifier extends Notifier<VoiceState> {
   void _onAmplitude(Amplitude event) {
     if (!state.voiceModeActive) return;
 
+    final db = event.current;
+    final validDb = !(db.isNaN || db.isInfinite);
+
+    // Normalize dB to 0..1 for the pulse animation. -60dB is dead-quiet,
+    // 0dB is peak; we clamp and bias so the button visibly breathes even
+    // on soft speech without exploding on loud input.
+    if (validDb) {
+      final norm = ((db + 60.0) / 60.0).clamp(0.0, 1.0);
+      if ((norm - state.amplitude).abs() > 0.02) {
+        state = state.copyWith(amplitude: norm);
+      }
+      if (db > _peakDb) _peakDb = db;
+    }
+
     final elapsed =
         DateTime.now().millisecondsSinceEpoch - _recordingStartMs;
+    // Grace period at the start — let the user begin speaking before we
+    // start silence-counting. Also suppresses any false triggers while
+    // the native recorder is still warming up.
+    if (elapsed < _graceMs) return;
     if (elapsed < _minRecordingMs) return;
 
-    final db = event.current;
-    // Guard against NaN / ±Infinity which can arrive on some Android devices
-    // when the recorder is initialising. Treat invalid readings as silence.
-    final isSilent = db.isNaN || db.isInfinite || db < _silenceThresholdDb;
+    // Dynamic threshold once we've seen real speech; static fallback
+    // before that so a dead-silent session doesn't spin forever.
+    final threshold =
+        _peakDb > _dynamicArmDb ? _peakDb - _dropFromPeakDb : _fallbackThresholdDb;
+    final isSilent = !validDb || db < threshold;
 
     if (isSilent) {
       _silenceMs += 200;

lib/screens/briefing/briefing_screen.dart

@@ -376,6 +376,7 @@ class _BriefingScreenState extends ConsumerState<BriefingScreen>
                       VoiceMicButton(
                         mode: voiceState.mode,
                         voiceModeActive: voiceState.voiceModeActive,
+                        amplitude: voiceState.amplitude,
                         onTap: _toggleVoiceMode,
                       ),
                       const SizedBox(width: 6),

lib/screens/chat/chat_screen.dart

@@ -267,6 +267,7 @@ class _ChatScreenState extends ConsumerState<ChatScreen>
                   VoiceMicButton(
                     mode: voiceState.mode,
                     voiceModeActive: voiceState.voiceModeActive,
+                    amplitude: voiceState.amplitude,
                     onTap: _toggleVoiceMode,
                   ),
                   const SizedBox(width: 6),

lib/widgets/voice_mic_button.dart

@@ -5,51 +5,29 @@ import '../providers/voice_provider.dart';
 /// Animated mic button that reflects the current [VoiceMode].
 ///
 /// - idle: muted background, mic_none icon
-/// - recording: red with pulsing shadow ring
+/// - recording: red, pulses with live [amplitude] for real-time feedback
 /// - transcribing: indigo with spinner
 /// - playing: indigo with volume_up icon
-class VoiceMicButton extends StatefulWidget {
+class VoiceMicButton extends StatelessWidget {
   final VoiceMode mode;
   final bool voiceModeActive;
+  /// Live mic amplitude 0.0–1.0 while recording. Drives the button scale
+  /// and glow so the user has obvious feedback that audio is being picked
+  /// up. Ignored when not in [VoiceMode.recording].
+  final double amplitude;
   final VoidCallback? onTap;
 
   const VoiceMicButton({
     super.key,
     required this.mode,
     required this.voiceModeActive,
+    this.amplitude = 0.0,
     this.onTap,
   });
 
-  @override
-  State<VoiceMicButton> createState() => _VoiceMicButtonState();
-}
-
-class _VoiceMicButtonState extends State<VoiceMicButton>
-    with SingleTickerProviderStateMixin {
-  late AnimationController _pulseController;
-  late Animation<double> _pulseAnimation;
-
-  @override
-  void initState() {
-    super.initState();
-    _pulseController = AnimationController(
-      vsync: this,
-      duration: const Duration(milliseconds: 900),
-    )..repeat(reverse: true);
-    _pulseAnimation = Tween<double>(begin: 1.0, end: 1.25).animate(
-      CurvedAnimation(parent: _pulseController, curve: Curves.easeInOut),
-    );
-  }
-
-  @override
-  void dispose() {
-    _pulseController.dispose();
-    super.dispose();
-  }
-
   Color _bgColor(BuildContext context) {
     final cs = Theme.of(context).colorScheme;
-    return switch (widget.mode) {
+    return switch (mode) {
       VoiceMode.recording => const Color(0xFFEF4444),
       VoiceMode.transcribing || VoiceMode.playing => cs.primary,
       VoiceMode.idle => cs.surfaceContainerHighest,
@@ -58,11 +36,10 @@ class _VoiceMicButtonState extends State<VoiceMicButton>
 
   Widget _icon(BuildContext context) {
     final cs = Theme.of(context).colorScheme;
-    final iconColor = widget.mode == VoiceMode.idle
-        ? cs.onSurfaceVariant
-        : Colors.white;
+    final iconColor =
+        mode == VoiceMode.idle ? cs.onSurfaceVariant : Colors.white;
 
-    return switch (widget.mode) {
+    return switch (mode) {
       VoiceMode.transcribing => SizedBox(
           width: 18,
           height: 18,
@@ -78,14 +55,14 @@ class _VoiceMicButtonState extends State<VoiceMicButton>
 
   @override
   Widget build(BuildContext context) {
-    final isRecording = widget.mode == VoiceMode.recording;
+    final isRecording = mode == VoiceMode.recording;
 
     final button = Material(
       color: _bgColor(context),
       shape: const CircleBorder(),
       child: InkWell(
         customBorder: const CircleBorder(),
-        onTap: widget.onTap,
+        onTap: onTap,
         child: SizedBox(
           width: 40,
           height: 40,
@@ -96,22 +73,30 @@ class _VoiceMicButtonState extends State<VoiceMicButton>
 
     if (!isRecording) return button;
 
-    return AnimatedBuilder(
-      animation: _pulseAnimation,
-      builder: (_, child) => Container(
-        decoration: BoxDecoration(
-          shape: BoxShape.circle,
-          boxShadow: [
-            BoxShadow(
-              color: const Color(0xFFEF4444).withValues(alpha: 0.35),
-              blurRadius: 8 * _pulseAnimation.value,
-              spreadRadius: 2 * _pulseAnimation.value,
-            ),
-          ],
-        ),
-        child: child,
+    // Base pulse so silence still breathes (0.1 floor), scale + glow climb
+    // linearly with live amplitude.
+    final amp = amplitude.clamp(0.0, 1.0);
+    final pulse = 0.1 + amp * 0.9;
+
+    return AnimatedContainer(
+      duration: const Duration(milliseconds: 120),
+      curve: Curves.easeOut,
+      decoration: BoxDecoration(
+        shape: BoxShape.circle,
+        boxShadow: [
+          BoxShadow(
+            color: const Color(0xFFEF4444).withValues(alpha: 0.2 + pulse * 0.3),
+            blurRadius: 6 + pulse * 14,
+            spreadRadius: 1 + pulse * 5,
+          ),
+        ],
+      ),
+      child: AnimatedScale(
+        scale: 1.0 + pulse * 0.18,
+        duration: const Duration(milliseconds: 120),
+        curve: Curves.easeOut,
+        child: button,
       ),
-      child: button,
     );
   }
 }