[camera_android_camerax] Retrieve lens direction from CameraX directly

[camsim99]

Changes manual detection of the camera direction via filtering to querying it directly from the camera info.

Fixes flutter/flutter#118730.

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[gemini-code-assist]

Code Review

This pull request refactors the camera lens direction detection by querying it directly from CameraX's CameraInfo instead of using a manual filtering workaround. This simplifies the code, removes a TODO, and improves maintainability. The changes are consistently applied across Dart and native Android code, including updates to pigeon files and tests.

I've found a critical issue in the Dart code where break statements are missing in a switch block, which will cause incorrect behavior. I've also provided a couple of suggestions to modernize the Java code by using switch expressions for better readability. Overall, this is a valuable simplification, and with the suggested fixes, it will be a great improvement.

[gemini-code-assist]

For improved conciseness and readability, you can use a Java switch expression here, as the project's Java version supports it. This modern language feature can make the code more streamlined.

    return switch (pigeonInstance.getLensFacing()) {
      case CameraSelector.LENS_FACING_FRONT -> LensFacing.FRONT;
      case CameraSelector.LENS_FACING_BACK -> LensFacing.BACK;
      case CameraSelector.LENS_FACING_EXTERNAL -> LensFacing.EXTERNAL;
      default -> LensFacing.UNKNOWN;
    };

[camsim99]

Indifferent. Also I think our formatter is too outdated for this, so this would require an update to that tool. Tried this locally and I get errors.

[gemini-code-assist]

Similar to the implementation in CameraInfoProxyApi, you can use a Java switch expression here in the test to make the code more concise and readable. This also helps keep the test code style consistent with the implementation.

      LensFacing expected = 
          switch (testedLensFacingValue) {
            case CameraSelector.LENS_FACING_BACK -> LensFacing.BACK;
            case CameraSelector.LENS_FACING_FRONT -> LensFacing.FRONT;
            case CameraSelector.LENS_FACING_EXTERNAL -> LensFacing.EXTERNAL;
            default -> LensFacing.UNKNOWN;
          };