feat: integrate authored nightdrive soundtrack

src/audio/journey-music-state.ts

@@ -0,0 +1,26 @@
+import type { AudioJourneyState } from '@/audio/types';
+
+const JOURNEY_MUSIC = Object.freeze({
+  start: { bias: 'open', entryPhrase: 0 },
+  profile: { bias: 'open', entryPhrase: 1 },
+  experience: { bias: 'shadow', entryPhrase: 2 },
+  infrastructure: { bias: 'shadow', entryPhrase: 3 },
+  'selected-builds': { bias: 'lift', entryPhrase: 4 },
+  'additional-work': { bias: 'lift', entryPhrase: 5 },
+  toolkit: { bias: 'resolve', entryPhrase: 6 },
+  contact: { bias: 'resolve', entryPhrase: 7 },
+} as const);
+
+export function resolveJourneyMusicState(sectionId: string, intensity = 0): AudioJourneyState {
+  const chapter = Object.hasOwn(JOURNEY_MUSIC, sectionId)
+    ? JOURNEY_MUSIC[sectionId as keyof typeof JOURNEY_MUSIC]
+    : JOURNEY_MUSIC.start;
+  const finiteIntensity = Number.isFinite(intensity) ? intensity : 0;
+  return Object.freeze({
+    ...chapter,
+    atStart: sectionId === 'start',
+    intensity: Math.min(1, Math.max(0, finiteIntensity)),
+  });
+}
+
+export const DEFAULT_AUDIO_JOURNEY_STATE = resolveJourneyMusicState('start');