[camera] Adds support for video stabilization

[ruicraveiro]

Implements getSupportedVideoStabilizationModes() and setVideoStabilizationMode() methods in CameraController.

Address issue flutter/flutter#89525.
It is the camera sub-PR for #7108.

Pre-Review Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
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• I linked to at least one issue that this PR fixes in the description above.
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• I added new tests to check the change I am making, or I have commented below to indicate which test exemption this PR falls under¹.
• All existing and new tests are passing.

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[gemini-code-assist]

Code Review

This pull request introduces support for video stabilization by adding getSupportedVideoStabilizationModes() and setVideoStabilizationMode() to the CameraController. The implementation includes updating CameraValue to store the current stabilization mode and providing comprehensive unit tests for the new functionality. The changes are well-structured and thoroughly tested. I have a couple of minor suggestions for improvement.