Update `CHANGELOG` (flutter#176654)

Updates `CHANGELOG` to include the two cherry picks in the 3.35.6 hotfix stable release:

flutter#176520
flutter#176359

**Note**: The Flutter team is currently trialing the use of [Gemini Code Assist for GitHub](https://developers.google.com/gemini-code-assist/docs/review-github-code). Comments from the `gemini-code-assist` bot should not be taken as authoritative feedback from the Flutter team. If you find its comments useful you can update your code accordingly, but if you are unsure or disagree with the feedback, please feel free to wait for a Flutter team member's review for guidance on which automated comments should be addressed.

Changelog entry for 3.35.5 (flutter#176103)

Changelog update for stable hotfix. These are the cherry picks:

flutter#176030
flutter#176048

engine version update for 3.37.0-0.1 (flutter#175445)

engine version update (flutter#175422)

https://ci.chromium.org/ui/p/dart-internal/builders/flutter/Linux%20flutter_release/168/overview 

Release engine version check failed.

Bump engine version for Flutter 3.37 (flutter#175081)

Update engine version for Flutter 3.35.3 stable hotfix. (flutter#174901)

[3.36 CP] Add a 'bad' commit to the beta, to be reverted. (flutter#17…

…4658)

This is innocuous, but we can download it from the SDK archive to ensure the file exists/does not exist.

Towards flutter#172011.

[3.36] CP flutter#174459 (Fix bug in test_golden_comparator) (flutter…

…#174603)

Manual CP for flutter#174459.

[3.36] CP flutter#174459 (Fix bug in test_golden_comparator) (flutter…

…#174603)

Manual CP for flutter#174459.

Prepare hotfixes for `3.36.X` (flutter#174380)

... just an `engine.version` is needed (today).