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>

api/tests/integration/test_waveform_peaks_schema.py

@@ -0,0 +1,49 @@
+"""Integration tests for waveform peaks stored inline in audio_versions."""
+
+import pytest
+
+from tests.factories import create_audio_version, create_band, create_member, create_song
+
+
+@pytest.mark.asyncio
+@pytest.mark.integration
+async def test_audio_version_stores_waveform_peaks(db_session, current_member):
+    """AudioVersion can store waveform_peaks and waveform_peaks_mini JSONB data."""
+    from rehearsalhub.repositories.audio_version import AudioVersionRepository
+
+    band = await create_band(db_session, creator_id=current_member.id)
+    song = await create_song(db_session, band_id=band.id, creator_id=current_member.id)
+    version = await create_audio_version(db_session, song_id=song.id)
+
+    peaks_500 = [float(i) / 500 for i in range(500)]
+    peaks_100 = [float(i) / 100 for i in range(100)]
+
+    repo = AudioVersionRepository(db_session)
+    updated = await repo.update(
+        version,
+        waveform_peaks=peaks_500,
+        waveform_peaks_mini=peaks_100,
+    )
+    await db_session.commit()
+
+    fetched = await repo.get_by_id(updated.id)
+    assert fetched is not None
+    assert fetched.waveform_peaks is not None
+    assert len(fetched.waveform_peaks) == 500
+    assert fetched.waveform_peaks_mini is not None
+    assert len(fetched.waveform_peaks_mini) == 100
+    assert fetched.waveform_peaks[0] == pytest.approx(0.0)
+    assert fetched.waveform_peaks[1] == pytest.approx(1 / 500)
+
+
+@pytest.mark.asyncio
+@pytest.mark.integration
+async def test_audio_version_peaks_default_null(db_session, current_member):
+    """waveform_peaks and waveform_peaks_mini are null by default."""
+    band = await create_band(db_session, creator_id=current_member.id)
+    song = await create_song(db_session, band_id=band.id, creator_id=current_member.id)
+    version = await create_audio_version(db_session, song_id=song.id)
+    await db_session.commit()
+
+    assert version.waveform_peaks is None
+    assert version.waveform_peaks_mini is None