Task 13's has_recent_tracing_gap query used .astext on a generic JSON
column, which raises AttributeError at runtime. The choreographer's
exception handler swallowed it, leaving the strike-count reset
permanently inert in production. Migrate the column to JSONB (which
supports .astext + GIN indexing for future audit queries), update the
ORM, and add a real-DB integration test that would have caught this.
