feat(payments): reuse pending provider payments

backend/db/migrator.py

@@ -1155,6 +1155,13 @@ def _migration_0035_add_subscription_promo_expiry_flag(connection: Connection) -
         )
 
 
+def _migration_0036_add_provider_payment_url(connection: Connection) -> None:
+    inspector = inspect(connection)
+    columns: Set[str] = {col["name"] for col in inspector.get_columns("payments")}
+    if "provider_payment_url" not in columns:
+        connection.execute(text("ALTER TABLE payments ADD COLUMN provider_payment_url VARCHAR"))
+
+
 MIGRATIONS: List[Migration] = [
     Migration(
         id="0001_add_channel_subscription_fields",
@@ -1342,6 +1349,11 @@ MIGRATIONS: List[Migration] = [
         description="Suppress multi-day expiry reminders for trial and bonus subscriptions",
         upgrade=_migration_0035_add_subscription_promo_expiry_flag,
     ),
+    Migration(
+        id="0036_add_provider_payment_url",
+        description="Persist provider payment links for reusable pending payments",
+        upgrade=_migration_0036_add_provider_payment_url,
+    ),
 ]