Feature 12: Regular dinners and onboarding (#94)

Co-authored-by: dev_agent <dev_agent@cubecraftlabs.com>

migrations/0010_dinner_grounding_revision.sql

@@ -0,0 +1,7 @@
+-- 0010_dinner_grounding_revision: each ground_dinner job carries the
+-- dinner's grounding_revision when it was enqueued, and records its result
+-- only while the dinner still has that revision. Renaming a pending dinner
+-- raises the revision before enqueuing the job for the new name, so an
+-- earlier job — queued or running — can no longer write the dinner.
+
+ALTER TABLE dinners ADD COLUMN grounding_revision INTEGER NOT NULL DEFAULT 0;