Review and update integration tests for Tizen plugins

[seungsoo47]

Background / Purpose

The integration tests of several Tizen plugins have drifted from their
upstream counterparts or only cover a thin slice of the API. This issue tracks
a systematic pass to bring each testable plugin's integration tests up to date,
so that they reflect the current behavior and are actually runnable on Tizen
devices/emulators.

Scope (per plugin)

• Identify the upstream package and the exact version the Tizen plugin targets.
• For plugins that wrap an upstream package: port the test cases from that
  upstream version that can actually run on Tizen, excluding platform-specific
  cases (Android/iOS/macOS-gated) that don't apply, and consolidate them into
  the single example/integration_test/<plugin>_test.dart.
• For Tizen-specific plugins (or where upstream tests don't apply): add
  regression tests over the public API.
• Validate on a Tizen device and/or emulator.

Target plugins (testable in .github/recipe.yaml)

• audioplayers — [audioplayers] Update integration tests to upstream v6.6.0 #1036
• connectivity_plus — already covered; no Tizen-runnable cases to add
• device_info_plus — [device_info_plus] Add regression integration tests #1038
• flutter_secure_storage — [flutter_secure_storage] Update integration tests based on upstream v10.2.0 #1040
• flutter_tts — [flutter_tts] Add integration tests for the supported TTS APIs #1041
• integration_test — already covered; no Tizen-runnable cases to add
• keyboard_detection — [keyboard_detection] Add regression integration tests #1042
• messageport — [messageport] Add regression integration tests #1043
• package_info_plus — already covered; no Tizen-runnable cases to add
• path_provider — already covered; no Tizen-runnable cases to add
• shared_preferences — [shared_preferences] Add integration tests based on upstream v2.5.5 #1047
• sqflite — already covered; no Tizen-runnable cases to add
• tizen_app_manager — [tizen_app_manager] Add integration tests #1049
• tizen_audio_manager — [tizen_audio_manager] Add regression integration tests #1050
• tizen_bundle — [tizen_bundle] Add integration tests #1051
• tizen_package_manager — [tizen_package_manager] Add integration tests and fix icon path handling #1055
• tizen_rpc_port — [tizen_rpc_port] Add integration tests and fix unsigned byte read #1054
• tizen_window_manager — [tizen_window_manager] Add regression integration tests #1053
• url_launcher — already covered; no Tizen-runnable cases to add
• wakelock_plus — already covered; no Tizen-runnable cases to add

Other plugins (in .github/recipe.yaml)

• permission_handler
• google_sign_in
• firebase_core
• tizen_log
• tizen_notification
• flutter_webrtc
• geolocator
• in_app_purchase
• network_info_plus
• video_player_avplay
• video_player_videohole
• tizen_app_control
• video_player
• webview_flutter
• webview_flutter_lwe
• flutter_inappwebview
• google_maps_flutter

Notes

• Validation runs on tv and/or common targets via flutter-tizen drive.