feat: Add build info and localization for entry app

- Introduced buildinfo.json5 to enable impeller feature.
- Added Chinese localization strings in string.json for module description and entry ability.
- Created Ability.test.ets for unit testing of ability functionalities.
- Implemented List.test.ets to run the ability tests.
- Developed TestAbility.ets to manage test execution and lifecycle events.
- Created Index.ets as a testability page with UI components.
- Added OpenHarmonyTestRunner.ts for managing test execution in OpenHarmony.
- Defined module.json5 for entry_test module configuration.
- Established color.json and string.json for base resources.
- Included icon.png for the test module.
- Created test_pages.json to define testability page sources.
- Configured hvigor and oh-package.json5 for project setup.
- Updated pubspec.yaml and related files to downgrade Dart SDK to 3.11.0 and adjust dependencies.
- Added PowerShell script to enable OpenHarmony Flutter toolchain.
- Updated multiple package pubspec.yaml files to align with Dart SDK version 3.11.0 and adjust dependencies accordingly.

app/ohos/entry/build-profile.json5

@@ -0,0 +1,15 @@
+
+{
+  "apiType": 'stageMode',
+  "buildOption": {
+  },
+  "targets": [
+    {
+      "name": "default",
+      "runtimeOS": "HarmonyOS"
+    },
+    {
+      "name": "ohosTest",
+    }
+  ]
+}