Run the mypy pre-commit hook the same way as CI

[agners]

Proposed change

Run the mypy pre-commit hook the same way CI does, with mypy supervisor.

mypy is a whole-program checker, but the hook was configured to check only the changed files (the default pass_filenames behavior) and added --ignore-missing-imports. Neither matches the CI command (mypy supervisor), which leads to two problems:

• Different results than CI. Checking only the changed files instead of the whole package can both miss and invent errors compared to a full run, so the hook and CI can disagree. See python/mypy#13916 for the whole-program-vs-per-file rationale.
• Intermittent INTERNAL ERROR crashes. When several supervisor/ files change, pre-commit splits the file list and runs the hook concurrently. Since mypy 2.0 the SQLite cache is enabled by default, and the parallel mypy processes race on the shared .mypy_cache/cache.db: SQLite reports database is locked (python/mypy#21525), and an interrupted write can leave the database malformed. This is the failure mode that the cache-cleanup runbook in Add mypy cache-fix skill documentation #6971 works around; this PR addresses the root cause instead.

The fix aligns the hook with CI:

• pass_filenames: false and an explicit supervisor target so the hook always checks the whole package in a single invocation.
• require_serial: true as a safeguard against pre-commit ever running the hook concurrently.
• Drop --ignore-missing-imports, which CI does not use and which is redundant anyway: [tool.mypy] already disables the import-not-found and import-untyped error codes.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature (which adds functionality to the supervisor)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue: python/mypy#21525, python/mypy#13916, and Add mypy cache-fix skill documentation #6971
• Link to documentation pull request:
• Link to cli pull request:
• Link to client library pull request:

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• The code has been formatted using Ruff (ruff format supervisor tests)
• Tests have been added to verify that the new code works.

If API endpoints or add-on configuration are added/changed:

• Documentation added/updated for developers.home-assistant.io
• CLI updated (if necessary)
• Client library updated (if necessary)