[boyfeiyu]

Fixes #70.

On Windows and universal platforms, stripping edge spaces or trailing periods can expose a reserved filename: sanitize_filename(" AUX") currently returns AUX. Recheck reserved names after that cleanup and use the existing reserved-name handler for filename and filepath components.

Keep the initial validation so custom names containing edge spaces, such as additional_reserved_names=[" CUSTOM"], still match and invoke their handler. Earlier fixes in #72, #73 and #74 were closed without merging; this replacement covers the compatibility case raised on #74 while retaining the existing handler behavior.

Tests cover exposed reserved names, extensions, str/Path inputs, path components, custom names with edge spaces, handler behavior and Linux controls. API docstrings describe the matching order.

Validation on macOS arm64 / CPython 3.9.6:

• Full suite: 4222 passed, 17 skipped; 110 additional review scenarios passed.
• Type, formatting, spelling, docs, package build and metadata checks passed.
• Ruff lint has existing failures: 129 diagnostics on the base, 128 here, with no new diagnostics.

The cross-platform interpreter matrix has not been run locally.

[agammann]

I exercised the Windows and universal cases where trimming exposes reserved names, including custom names that contain edge spaces. The sanitizer now applies the reserved-name handler after that trim while retaining the first validation for custom names; the focused filename tests pass (28 passed). The documentation also states when the second check occurs. This looks good to me.