Reject non-normalized names in filename parsers

[kocaemre]

Summary

• Preserve the NormalizedName invariant for parsed wheel and sdist filenames.
• Reject filename project names whose canonicalized value is not accepted by is_normalized_name.
• Move the non-ASCII filename cases from accepted wheel examples to invalid filename coverage and add matching sdist coverage.

Closes #1350.

Verification

RED:

• python3 -m pytest tests/test_utils.py::test_parse_wheel_filename_rejects_names_that_are_not_normalized -q failed before the fix with Failed: DID NOT RAISE <class 'packaging.utils.InvalidWheelFilename'>.

GREEN:

• python3 -m pytest tests/test_utils.py -q → 79 passed
• python3 -m pytest -q → 62425 passed, 427 deselected
• python3 -m ruff check src/packaging/utils.py tests/test_utils.py → All checks passed
• python3 -m ruff format --check src/packaging/utils.py tests/test_utils.py → 2 files already formatted
• python3 -m py_compile src/packaging/utils.py tests/test_utils.py
• git diff --check

Duplicate preflight

• Issue parse_wheel_filename can return a project name that fails is_normalized_name #1350 is open and unassigned.
• Checked open PRs for parse_wheel_filename can return a project name that fails is_normalized_name #1350, non-ASCII/unicode names, parse_wheel_filename, parse_sdist_filename, and is_normalized_name.
• Existing PR feat: add strict wheel filename validation #1309 is scoped to opt-in strict wheel validation for Bug: parse_wheel_filename permits non-normalized versions. #873 and explicitly does not change default parsing or sdist parsing, so this remains a focused parse_wheel_filename can return a project name that fails is_normalized_name #1350 fix.

[sbidoul]

I believe the linked issues needs discussion before considering a PR.

[kocaemre]

Thanks — moved the rationale/options to the linked issue for discussion: #1350 (comment)