Add pre-commit hook to verify static analysis passes & format is correct

[camsim99]

Adds a pre-commit hook that you can install to verify that dart analyze --fatal-infos and the package format are correct when you make a call to git commit. Intended to ensure agents commit code that meets are quality standards.

Also makes the following updates the plugins tool:

• Adds --run-on-staged-packages flag that allows the command to only run on files with staged changes. This flag cannot be run with any other flags that filter packages where the command runs (like --run-on-dirty-packages)
• Adds optimization to the format tool to avoid invoking native tool chains to format when non-native files are modified

Miscellaneous notes:

• script/githooks/bin/install_hooks.dart is the script to install the hook that devs would need to run to use it.
• I modeled the new githooks directory like https://github.com/flutter/flutter/tree/master/engine/src/flutter/tools/githooks to make it easier for folks to add new hooks

Pre-Review Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the AI contribution guidelines and understand my responsibilities, or I am not using AI tools.
• I read the Tree Hygiene page, which explains my responsibilities.
• I read and followed the relevant style guides and ran the auto-formatter.
• I signed the CLA.
• The title of the PR starts with the name of the package surrounded by square brackets, e.g. [shared_preferences]
• I linked to at least one issue that this PR fixes in the description above.
• I followed the version and CHANGELOG instructions, using semantic versioning and the repository CHANGELOG style, or I have commented below to indicate which documented exception this PR falls under¹.
• I updated/added any relevant documentation (doc comments with ///).
• 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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Footnotes

1. Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling. ↩↩²

[gemini-code-assist]

Code Review

This pull request introduces a new githooks Dart package to automate pre-commit checks, including formatting and static analysis, for staged files. The package includes an installation script, a pre-commit command runner, and associated unit tests. Review feedback highlights a potential infinite loop on Windows when locating the .git directory, raw ANSI escape sequences being printed without verifying terminal support, the use of loose any version constraints in pubspec.yaml, and redundant dead code in the test mocks.

[reidbaker]

Would you be willing to file a bug to have me/us investigate why the performance gap was so large.

[auto-submit]

autosubmit label was removed for flutter/packages/11941, because - The status or check suite Dashboard Checks has failed. Please fix the issues identified (or deflake) before re-applying this label.

[auto-submit]

autosubmit label was removed for flutter/packages/11941, because - The status or check suite Dashboard Checks has failed. Please fix the issues identified (or deflake) before re-applying this label.