fix(static): support HEAD without opening files

[paulkagiri]

Summary of Changes

Static routes now handle HEAD separately from GET: they compute the same response metadata without opening a file stream, preserve range headers for ranged HEAD requests, and return 405 Method Not Allowed for unsupported methods. OPTIONS now advertises both GET and HEAD.

Related Issues

Closes #2337

Pull Request Checklist

• Applied changes to both WSGI and ASGI code paths and interfaces (where applicable).
• Added tests for changed code.
• Performed automated tests and code quality checks by running tox.
• Prefixed code comments with GitHub nick and an appropriate prefix.
• Coding style is consistent with the rest of the framework.
• Updated documentation for changed code.
• Changes have towncrier news fragments under docs/_newsfragments/, with the file name format {issue_number}.{fragment_type}.rst.
• LLM output, if any, has been carefully reviewed and tested by a human developer.

Testing performed:

• python -m pytest tests/test_static.py -q
• git diff --check

[vytas7]

Hey, and thanks for this PR.
Please check the failing CI, most of the gates fail on your changes.