- Add is_pinned(), pin(), _load_meta(), _save_meta() to L1CacheManager
- Update can_delete() and can_discard_activity() to check local pinned status
- Update run deletion endpoints (API and UI) to check pinned metadata
- Remove L2 shared check fallback from run deletion
- Fix L2SharedChecker to return True on error (safer - prevents accidental deletion)
- Update tests for new pinned behavior
When items are published to L2, the publish flow marks them as pinned
locally. This ensures items remain non-deletable even if L2 is unreachable,
and both outputs AND inputs of published runs are protected.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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