feat: add opt-in procedural drive audio

src/components/AppShell.vue

@@ -12,6 +12,7 @@ import SceneCanvas from './SceneCanvas.vue';
 import SiteNavigation from './SiteNavigation.vue';
 import ToolkitGrid from './ToolkitGrid.vue';
 import { useAdaptiveQuality } from '@/composables/useAdaptiveQuality';
+import { useAudioEngine } from '@/composables/useAudioEngine';
 import { useJourneySections } from '@/composables/useJourneySections';
 import { useKeyboardNavigation } from '@/composables/useKeyboardNavigation';
 import { useMotionPreferences } from '@/composables/useMotionPreferences';
@@ -43,6 +44,11 @@ const journey = useJourneySections(
   navigation.state,
   computed(() => motion.policy.value.allowSceneRequest),
 );
+const audio = useAudioEngine({
+  intensity: computed(() => journey.value.acceleration),
+  volume: motion.volume,
+  setVolume: motion.setVolume,
+});
 const sceneState = shallowRef<SceneHostState>('idle');
 const pageLifecycle = shallowRef<'active' | 'frozen' | 'disposed'>('active');
 const controlsReady = shallowRef(false);
@@ -175,9 +181,16 @@ onUnmounted(() => removePageListeners());
     :policy="displayedPolicy"
     :maximum-quality="controlsReady ? motion.maximumQuality.value : 'high'"
     :scene-status="displayedSceneState"
+    :audio-state="audio.state.value"
+    :audio-muted="audio.muted.value"
+    :audio-volume="controlsReady ? motion.volume.value : 0.4"
     @pause="motion.setPaused(true)"
     @resume="motion.setPaused(false)"
     @enable="enableMotion"
     @quality-change="setQuality"
+    @audio-start="audio.startFromGesture"
+    @audio-resume="audio.resumeFromGesture"
+    @audio-mute-toggle="audio.toggleMuted"
+    @audio-volume-change="audio.setVolume"
   />
 </template>