Preserve draft metadata and dedupe composer image retries

- Reuse hidden draft threads while applying requested branch/worktree updates before navigation
- Export composer draft storage key and clone blob preview URLs when re-adding images after retry
- Deduplicate composer images by file signature (within and across calls) and add store tests for URL revoke behavior
c9995995a4Julius Marminge committed on 3/2/2026, 6:36:35 AM· committed by Julius Marmingeparent545a919
4 files changedLine totals unavailable