The LLM (Opus score stage / Haiku cards stage) can return None or empty
content, causing _salvage_objects to crash with
'NoneType' object has no attribute 'find' — which killed the curation
pipeline and returned zero matches to the user.
- Guard _salvage_objects and _salvage_kept against None/empty input
- Add explicit empty-content checks in both stages with logging
- Log content[:200] on unparseable score stage for QA diagnostics
28cacfcc7c