Refactor: Update error messages in user routes tests for clarity and consistency

src/services/db/flyer.db.test.ts

@@ -249,10 +249,11 @@ describe('Flyer DB Service', () => {
         mockClient.query
           .mockResolvedValueOnce({ rows: [{ store_id: 1 }] }) // findOrCreateStore
           .mockRejectedValueOnce(dbError); // insertFlyer fails
-        // The withTransaction helper will catch this and roll back
-        await expect(callback(mockClient as unknown as PoolClient)).rejects.toThrow(dbError);
-        // re-throw because withTransaction re-throws
-        throw dbError;
+        // The withTransaction helper will catch this and roll back.
+        // Since insertFlyer wraps the DB error, we expect the wrapped error message here.
+        await expect(callback(mockClient as unknown as PoolClient)).rejects.toThrow('Failed to insert flyer into database.');
+        // re-throw because withTransaction re-throws (simulating the wrapped error propagating up)
+        throw new Error('Failed to insert flyer into database.');
       });
 
       // The transactional function re-throws the original error from the failed step.