Build Wisp: on-device transcription studio (web + native, one codebase)

Private, offline speech-to-text that runs Whisper on the user's own device —
free, no account, no per-minute fees. Replaces Otter.ai / Rev.

- Pure, tested engine: chunking, overlap timestamp-stitching, exports
  (SRT/VTT/TXT/MD/JSON), WAV codec, resampler, job queue, model catalog (142 tests).
- Platform-abstracted TranscriptionEngine: transformers.js on web (loaded from
  CDN at runtime to dodge Metro's onnxruntime-web bundling limits), whisper.rn
  on native. Shared pipeline orchestrates decode -> chunk -> transcribe -> stitch.
- Cross-platform StorageRepo (Dexie web / expo-sqlite native), Zod-validated.
- UI: library + search, import, live-progress transcription, synced click-to-seek
  editor, multi-format export; model picker + privacy in settings.
- Web ships as a single-page PWA with COOP/COEP isolation for threaded WASM;
  Docker (nginx) image + Traefik compose for wisp.briggen.dev.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

vitest.config.ts

@@ -0,0 +1,12 @@
+import { defineConfig } from 'vitest/config';
+
+// Pure-engine tests run in Node. The repository contract tests pull in
+// `fake-indexeddb/auto`, which polyfills IndexedDB into the Node global, so
+// they run here too without a DOM.
+export default defineConfig({
+  test: {
+    environment: 'node',
+    include: ['src/lib/**/*.test.ts'],
+    globals: false,
+  },
+});