fix(prisma): explicitly drop Product_ownerId_fkey before NOT NULL

backend/prisma/migrations/20260502160000_product_owner_required/migration.sql

@@ -11,26 +11,8 @@ WHERE p.`ownerId` IS NULL;
 DELETE FROM `Product` WHERE `ownerId` IS NULL;
 
 -- Steg 3: Uppdatera foreign key constraint (droppa befintlig först)
--- Droppa befintlig FK på ownerId med dynamiskt namn (miljöer kan skilja sig).
+ALTER TABLE `Product`
-SET @fk_name := (
+  DROP FOREIGN KEY `Product_ownerId_fkey`;
-  SELECT kcu.CONSTRAINT_NAME
-  FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE kcu
-  WHERE kcu.TABLE_SCHEMA = DATABASE()
-    AND kcu.TABLE_NAME = 'Product'
-    AND kcu.COLUMN_NAME = 'ownerId'
-    AND kcu.REFERENCED_TABLE_NAME = 'User'
-  LIMIT 1
-);
-
-SET @drop_fk_sql := IF(
-  @fk_name IS NULL,
-  'SELECT 1',
-  CONCAT('ALTER TABLE `Product` DROP FOREIGN KEY `', @fk_name, '`')
-);
-
-PREPARE stmt_drop_fk FROM @drop_fk_sql;
-EXECUTE stmt_drop_fk;
-DEALLOCATE PREPARE stmt_drop_fk;
 
 -- Steg 4: Gör ownerId obligatoriskt
 ALTER TABLE `Product`