Preserve uploaded track metadata when publishing tracks

[raymondjacobson]

Summary

• publish DDEX-created tracks through SDK uploadTrackFiles + publishTrack so upload responses are preserved for chain metadata
• use the same helper for single tracks and album child tracks
• update focused publish tests to assert audio/image upload responses flow into publishTrack

Tests

• npx vitest run src/publishRelease.test.ts
• npm run tsc
• DB_URL=postgresql://postgres:test@127.0.0.1:40111/ddex_codex_track_publish_test npm test