Detect a .lake child renamed out and back in on Windows project inspection #403

On Windows, os.stat(path).st_ctime_ns is a directory's creation time, not its last change. So, according to the docstring of the token described below, the identity _directory_generation (autoform_cli/project/_snapshot.py) records for a directory may not change when a child is renamed out and back in while the decision files are captured; no test has shown this on a real Windows filesystem. On POSIX the change time covers that case.

Merge 216ad27b on #90's branch added a Windows-only token for the .lake directory's identity: _directory_change_token read the change time from FILE_BASIC_INFO through a directory handle (kernel32 CreateFileW with backup semantics, then GetFileInformationByHandleEx) and appended it to the identity. c5313fe0 took it only for directories and opened the handle without FILE_FLAG_OPEN_REPARSE_POINT, so it follows links as os.stat does. Its only test monkeypatched the token, and the change had nothing to do with #90's inventories or explorer, so 73ed9247 returned _snapshot.py and tests/test_project_inspect.py to main's bytes.

Proposal: bring the token back as its own PR, with a test on the Windows CI job that renames a real child out and back in during a capture and shows the snapshot notice it, which the monkeypatched test could not. The removed code is in git show 73ed92470 -- autoform_cli/project/_snapshot.py.