gh-150880: Normalize Windows scandir wildcard paths

[zainnadeem786]

Summary

On Windows, os.listdir() and os.scandir() append a wildcard before calling FindFirstFileW().

For paths with a trailing space, this changes the path from a final-component trailing-space case into an internal path component, so Windows no longer trims the space. This makes listdir() and scandir() behave differently from APIs such as open(), os.stat(), and os.path.exists().

This PR normalizes non-extended Windows base paths with GetFullPathNameW() before appending the wildcard used for enumeration.

Extended paths beginning with \\?\ continue to bypass normalization.

Changes

• Normalize only the wildcard path used by Windows listdir() and scandir().
• Preserve existing DirEntry.path construction behavior.
• Preserve extended-path semantics.
• Add regression coverage for trailing-space directory paths.

Tests

PCbuild\build.bat -p x64 -d
PCbuild\amd64\python_d.exe -m unittest -v test.test_os.test_os.TestScandir.test_windows_trailing_space_path
PCbuild\amd64\python_d.exe -m test test_os
PCbuild\amd64\python_d.exe -m test test_pathlib test_ntpath
git diff --check

Close #150880