Agent Skills: flutter-testing

Write unit, widget, and integration tests with robots, widget keys, and Patrol in Flutter. Use when writing Flutter unit tests, widget tests, or integration tests with Patrol. (triggers: **/test/**.dart, **/integration_test/**.dart, **/robots/**.dart, lib/core/keys/**.dart, test, patrol, robot, WidgetKeys, patrolTest, blocTest, mocktail)