init

backend/migrations/0004_notify.sql

@@ -0,0 +1,6 @@
+-- Phase 4: price-drop notifications.
+-- Tracks when we last emailed the owner that an item reached its target price.
+-- NULL = "armed": a future drop to/under target will notify. Stamped non-NULL
+-- after sending; cleared (re-armed) when the price rises back above target.
+ALTER TABLE items
+    ADD COLUMN notified_at TIMESTAMPTZ;