🔧 chore(dev): configure default Git hooks

[zrr1999]

Proposal summary

• Declare pre-commit and commit-msg in default_install_hook_types, so plain installation uses the repository configuration.
• Default ordinary file checks to pre-commit; retain the message hook’s explicit upstream commit-msg stage.

Linked discussion

Not applicable: repository hook configuration maintenance, with no SEP or language contract change.

Checklist

• I opened or linked a public Discussion or Issue for the pitch before submitting this draft SEP.
• I linked the canonical discussion thread.
• I used the correct SEP template for this proposal type.
• I updated front matter metadata and required sections.

Notes for reviewers

The SEP checklist above is not applicable to this tooling change.

• uvx prek validate-config prek.toml passed.
• Installed into a disposable Git repository without --hook-type, and verified the generated pre-commit and commit-msg shims.
• The configured commit-message stage accepts a valid title and rejects a message without the required emoji/type prefix.
• prek checks on all changed files and git diff --check passed.

Fresh CI cannot resolve the existing rumdl==0.1.63 dependency while preparing the rumdl-fmt hook, before the file checks run. The hook repository, revision, and arguments are unchanged from the base branch. See CI.