Renumber the frozen-name migration to 0019 (task 22f80eb6)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

migrations/0019_shopping_group_frozen_name.sql

@@ -0,0 +1,14 @@
+-- 0018_shopping_group_frozen_name: a Supply run frozen into the Supply
+-- archive keeps the names its dinners had when it was frozen. A dinner can
+-- be renamed at any time, so a frozen list reads each group's dinner name
+-- from frozen_dinner_name, never from the dinner, as 0012 does for a Pass.
+-- Only a group of a frozen list has one; a current list reads its dinners'
+-- names live. A list frozen before this takes its dinners' names now.
+
+ALTER TABLE shopping_groups ADD COLUMN frozen_dinner_name TEXT CHECK (frozen_dinner_name <> '');
+
+UPDATE shopping_groups
+SET frozen_dinner_name = (SELECT dinners.name FROM dinners WHERE dinners.id = shopping_groups.dinner_id)
+WHERE list_id IN (
+	SELECT id FROM shopping_lists WHERE status = 'archived' OR frozen_at IS NOT NULL
+);