Move diff parsing to worker pool with stable patch cache keys

- Wrap `DiffPanel` in `WorkerPoolContextProvider` and add a dedicated diffs worker
- Use content-based patch cache keys to stabilize `parsePatchFiles` caching
- Add tests for cache key stability, whitespace normalization, and content changes
5cfab38f31Julius Marminge committed on 2/19/2026, 5:59:17 AM· committed by Julius Marmingeparentba1a2db
4 files changedLine totals unavailable