Three issues fixed:
1. asBytes() helper for []interface{} → []byte conversion — same
float64 deserialization issue as numeric fields. Cover art data
from the frontend arrives as []interface{} of float64, not []byte.
2. DB sync for cover art — was a placeholder no-op. Now saves image
to covers cache dir (content-hash dedup + thumbnail generation),
upserts cover_art row, and updates release_groups.cover_art_id.
Clear sets cover_art_id to NULL on linked release groups.
3. Frontend ReadFile returns base64 string (Go []byte JSON encoding),
not number[]. Decode with atob() before creating Uint8Array for
preview blob URL.
yonlu
d7c2965752