Fix plugin purchase 500 when subscription catalog columns are missing.

Co-authored-by: Cursor <cursoragent@cursor.com>

prisma/migrations/20260910120000_plugin_subscription_catalog_key/migration.sql

@@ -0,0 +1,13 @@
+-- Catalog linkage on plugin_subscriptions was in schema.prisma without a
+-- CREATE COLUMN migration. Remote store GET swallows the missing column;
+-- POST create did not, so purchase requests returned HTTP 500.
+
+ALTER TABLE "plugin_subscriptions"
+  ADD COLUMN IF NOT EXISTS "setting_key" VARCHAR(50);
+ALTER TABLE "plugin_subscriptions"
+  ADD COLUMN IF NOT EXISTS "auto_cut_on_expiry" BOOLEAN NOT NULL DEFAULT false;
+ALTER TABLE "plugin_subscriptions"
+  ADD COLUMN IF NOT EXISTS "alert_marks" JSONB;
+
+CREATE INDEX IF NOT EXISTS "plugin_subscriptions_setting_key_idx"
+  ON "plugin_subscriptions"("setting_key");