fix: gate native Tauri audio backend

src-tauri/src/commands/audio.rs

@@ -10,9 +10,9 @@ use tauri::{Emitter, State};
 
 use crate::engine::{
     audio_io, AudioDeviceInfo, ClipSchedule, ClipSource, CommandError, CountIn, Engine,
-    EngineConfig, EngineError, EngineStatus, LoopRegion, MetronomeConfig, PositionEmitter,
-    PunchRegion, TempoEvent, TempoMap, TimeSignatureEvent, TimeSignatureMap, TrackParams,
-    POSITION_EVENT_DEFAULT_INTERVAL,
+    EngineConfig, EngineError, EngineStatus, LoopRegion, MeterReading, MetronomeConfig,
+    PositionEmitter, PunchRegion, TempoEvent, TempoMap, TimeSignatureEvent, TimeSignatureMap,
+    TrackParams, POSITION_EVENT_DEFAULT_INTERVAL,
 };
 use crate::engine::slot::SlotHandle;
 
@@ -218,6 +218,27 @@ pub fn audio_set_master_volume(
     engine.set_master_volume(volume)
 }
 
+#[tauri::command]
+pub fn audio_get_track_meter(
+    handle: SlotHandle,
+    state: State<'_, EngineState>,
+) -> Result<MeterReading, CommandError> {
+    let mut engine = state
+        .0
+        .lock()
+        .map_err(|_| CommandError::Disconnected)?;
+    Ok(engine.get_track_meter(handle))
+}
+
+#[tauri::command]
+pub fn audio_get_master_meter(state: State<'_, EngineState>) -> Result<MeterReading, CommandError> {
+    let mut engine = state
+        .0
+        .lock()
+        .map_err(|_| CommandError::Disconnected)?;
+    Ok(engine.get_master_meter())
+}
+
 // ── Transport (3A) ──────────────────────────────────────────────────
 
 #[tauri::command]

src-tauri/src/lib.rs

@@ -5,7 +5,8 @@ use tauri::Manager;
 
 use crate::commands::audio::{
     audio_add_track, audio_clip_get_schedule, audio_clip_set_schedule,
-    audio_get_default_device, audio_get_engine_status, audio_list_devices,
+    audio_get_default_device, audio_get_engine_status, audio_get_master_meter,
+    audio_get_track_meter, audio_list_devices,
     audio_metronome_get_config, audio_metronome_set_config, audio_metronome_set_enabled,
     audio_remove_track, audio_set_master_volume, audio_set_track_params,
     audio_start_engine, audio_stop_engine, audio_transport_get_count_in,
@@ -55,6 +56,8 @@ pub fn run() {
             audio_remove_track,
             audio_set_track_params,
             audio_set_master_volume,
+            audio_get_track_meter,
+            audio_get_master_meter,
             audio_transport_play,
             audio_transport_stop,
             audio_transport_pause,