feat(path): implement node:path.win32 sub-namespace

[TheHypnoo]

Context

Perry's node:path runtime implements POSIX semantics (path.basename, path.dirname, path.parse, etc.) but does NOT expose the path.win32 sub-namespace — path.win32.<method> resolves to undefined on every method/property read, so any code path that depends on Windows-style separator handling (\\), drive letters (C:\\…), or UNC paths (\\\\server\\share) crashes or produces wrong output.

Surfaced by the granular node-suite/path/win32/* fixtures added under the per-method parity coverage work — five tests currently fail and are skip-listed in test-parity/known_failures.json pointing at this issue.

Scope

Implement the path.win32 namespace mirror of every POSIX method Perry already supports:

• path.win32.basename(p, [ext])
• path.win32.dirname(p)
• path.win32.extname(p)
• path.win32.format({root, dir, base, name, ext})
• path.win32.isAbsolute(p)
• path.win32.join(...segments)
• path.win32.normalize(p)
• path.win32.parse(p) → {root, dir, base, name, ext}
• path.win32.relative(from, to)
• path.win32.resolve(...segments)
• path.win32.sep (\\) and path.win32.delimiter (;) constants
• path.win32.toNamespacedPath(p)
• path.win32.matchesGlob(p, glob)

Plus the Windows-specific rules each method enforces:

• Drive letters (C:\\foo) are absolute roots; relative-to-drive (C:foo) preserves the drive prefix without making the path absolute.
• UNC paths (\\\\server\\share\\…) keep the four-character root.
• \\\\?\\ device prefix paths are passed through normalize / parse intact.
• Both \\ and / count as separators on Windows.

Acceptance criterion

./run_parity_tests.sh --suite node-suite --module path reports PASS for all five win32 fixtures byte-for-byte against node --experimental-strip-types:

• node-suite/path/win32/basename-dirname
• node-suite/path/win32/join-normalize
• node-suite/path/win32/parse-format
• node-suite/path/win32/relative-resolve
• node-suite/path/win32/unc-and-drive

Remove the matching entries from test-parity/known_failures.json once the implementation lands.

Out of scope

path.posix is already wired (see crates/perry-runtime/src/path.rs); only the win32 mirror is missing.