- Migration adds last_used_at and run_count; existing prompts are estimated
from linked images (count, newest image time, else created_at). The
backfill only touches NULL rows, so it self-heals rows written after a
downgrade or an interrupted upgrade.
- Every node run records a use, including re-runs of an existing prompt;
a tracking failure is logged and never blocks generation.
- search_prompts/get_recent_prompts accept a whitelisted sort key
(last_used, created, run_count, rating, text); default stays newest first.
Refs #90
Vito Sansevero
6099d5eb23