[ci] feat: add mergify

[vermouth1992]

What does this PR do?

• Automatically at author if precommit fails.

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[vermouth1992]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds a Mergify rule to automatically comment on pull requests and add a label when the pre-commit check fails. My review identifies a potential point of failure in the new rule. The condition for triggering the rule is tied to a specific Python version, which makes it brittle. I've suggested using a regular expression to make the rule more robust against future changes in the CI environment. There are no other issues.

[gemini-code-assist]

The condition check-failure=pre-commit / pre-commit (3.12) is brittle because it is hardcoded to a specific Python version (3.12). If the Python version in the CI workflow is updated, this rule will silently stop working. To make this rule more robust and future-proof, it's better to use a regular expression that isn't tied to the specific version.

      - check-failure~=^pre-commit / pre-commit