feat(waveform): precompute and store peaks in DB for instant rendering

Store waveform peaks inline in audio_versions (JSONB columns) so WaveSurfer
can render the waveform immediately on page load without waiting for audio
decode. Adds a 100-point mini-waveform for version selector thumbnails.

Backend:
- Migration 0006: adds waveform_peaks and waveform_peaks_mini JSONB columns
- Worker generates both resolutions (500-pt full, 100-pt mini) during transcode
  and stores them directly in DB — replaces file-based waveform_url approach
- AudioVersionRead schema exposes both fields inline (no extra HTTP round-trip)
- GET /versions/{id}/waveform reads from DB; adds ?resolution=mini support

Frontend:
- audioService.initialize() accepts peaks and calls ws.load(url, Float32Array)
  so waveform renders instantly without audio decode
- useWaveform hook threads peaks option through to audioService
- PlayerPanel passes waveform_peaks from the active version to the hook
- New MiniWaveform SVG component (no WaveSurfer) renders mini peaks in the
  version selector buttons

Fix: docker-compose.dev.yml now runs alembic upgrade head before starting
the API server, so a fresh volume gets the full schema automatically.

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

web/src/services/audioService.test.ts

@@ -0,0 +1,125 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { AudioService } from "./audioService";
+
+// ── WaveSurfer mock ────────────────────────────────────────────────────────────
+
+const mockLoad = vi.fn();
+const mockOn = vi.fn();
+const mockUnAll = vi.fn();
+const mockDestroy = vi.fn();
+const mockGetDuration = vi.fn(() => 180);
+const mockSetOptions = vi.fn();
+const mockCreate = vi.fn();
+
+vi.mock("wavesurfer.js", () => ({
+  default: {
+    create: (opts: unknown) => {
+      mockCreate(opts);
+      return {
+        load: mockLoad,
+        on: mockOn,
+        unAll: mockUnAll,
+        destroy: mockDestroy,
+        getDuration: mockGetDuration,
+        setOptions: mockSetOptions,
+        isPlaying: vi.fn(() => false),
+      };
+    },
+  },
+}));
+
+// ── Zustand store mock ─────────────────────────────────────────────────────────
+
+vi.mock("../stores/playerStore", () => ({
+  usePlayerStore: {
+    getState: vi.fn(() => ({
+      isPlaying: false,
+      currentTime: 0,
+      duration: 0,
+      currentSongId: null,
+      currentBandId: null,
+      batchUpdate: vi.fn(),
+      setDuration: vi.fn(),
+      setCurrentSong: vi.fn(),
+    })),
+    subscribe: vi.fn(),
+  },
+}));
+
+// ── Helpers ────────────────────────────────────────────────────────────────────
+
+function makeContainer(): HTMLDivElement {
+  return document.createElement("div");
+}
+
+function triggerWaveSurferReady() {
+  // WaveSurfer fires the "ready" event via ws.on("ready", cb)
+  const readyCb = mockOn.mock.calls.find(([event]) => event === "ready")?.[1];
+  readyCb?.();
+}
+
+// ── Tests ──────────────────────────────────────────────────────────────────────
+
+describe("AudioService.initialize()", () => {
+  let service: AudioService;
+
+  beforeEach(() => {
+    AudioService.resetInstance();
+    service = AudioService.getInstance();
+    vi.clearAllMocks();
+    mockGetDuration.mockReturnValue(180);
+  });
+
+  afterEach(() => {
+    AudioService.resetInstance();
+  });
+
+  it("calls ws.load(url) without peaks when no peaks provided", async () => {
+    const container = makeContainer();
+    const url = "http://localhost/audio/song.mp3";
+
+    const initPromise = service.initialize(container, url);
+    triggerWaveSurferReady();
+    await initPromise;
+
+    expect(mockLoad).toHaveBeenCalledOnce();
+    const [calledUrl, calledPeaks] = mockLoad.mock.calls[0];
+    expect(calledUrl).toBe(url);
+    expect(calledPeaks).toBeUndefined();
+  });
+
+  it("calls ws.load(url, [Float32Array]) when peaks are provided", async () => {
+    const container = makeContainer();
+    const url = "http://localhost/audio/song.mp3";
+    const peaks = Array.from({ length: 500 }, (_, i) => i / 500);
+
+    const initPromise = service.initialize(container, url, peaks);
+    triggerWaveSurferReady();
+    await initPromise;
+
+    expect(mockLoad).toHaveBeenCalledOnce();
+    const [calledUrl, calledChannelData] = mockLoad.mock.calls[0];
+    expect(calledUrl).toBe(url);
+    expect(calledChannelData).toHaveLength(1);
+    expect(calledChannelData[0]).toBeInstanceOf(Float32Array);
+    expect(calledChannelData[0]).toHaveLength(500);
+    expect(calledChannelData[0][0]).toBeCloseTo(0);
+    expect(calledChannelData[0][499]).toBeCloseTo(499 / 500);
+  });
+
+  it("does not re-initialize for the same url and container", async () => {
+    const container = makeContainer();
+    const url = "http://localhost/audio/song.mp3";
+    const peaks = [0.5, 0.5, 0.5];
+
+    const p1 = service.initialize(container, url, peaks);
+    triggerWaveSurferReady();
+    await p1;
+
+    vi.clearAllMocks();
+
+    // Second call with same URL + container: should no-op
+    await service.initialize(container, url, peaks);
+    expect(mockLoad).not.toHaveBeenCalled();
+  });
+});