Introduces the flet_integration_test Dart package and RemoteWidgetTester for TCP-based remote control of Flutter integration tests. Updates FletTestApp in Python to support a new 'remote' test mode, allowing tests to be driven without launching a Flet app. Refactors test setup and teardown logic to support both local and remote modes, and exposes RemoteTester in the Python SDK.

Introduces a custom ChunkedLineDecoder for robust UTF-8 line splitting with max length enforcement in Dart and Python remote tester implementations. Updates iOS minimum deployment target to 13.0 in project files. Refactors remote tester logic to handle large messages and prevent buffer overflows.

Improves type annotations and refactors the set_default_subparser function to return the modified argument list. Adds a run() function for better testability and separates parser creation logic. The main entry point now calls run() and handles exit codes more cleanly.

Replaces usage of 'id' with 'finder_id' and adds support for 'finder_index' in tap, long_press, enter_text, and mouse_hover actions in RemoteWidgetTester. Also removes unused import from flutter_tester.dart.