Claude Obsidian v2.1.0 - Native Windows Compatibility

Native Windows Compatibility

Native Windows previously crashed on every vault command with
AttributeError: os has no attribute 'O_DIRECTORY' (#147). Now:

• Read-only works natively: inspection, dry-runs, and retrieval run on
  Windows with real equivalent safety checks (path-based alias auditing,
  lstat identity, symlink and junction rejection).
• Writes fail closed, cleanly: ERR UNSUPPORTED_PLATFORM (exit 2) before
  any side effect — use WSL for mutations.
• CRLF fixes for every platform: binary-mode reads end false hash
  mismatches, and retrieval no longer returns zero results on CRLF vaults.
• Windows CI: a new windows-smoke job plus a 16-test compatibility
  suite guard against regressions.

Full notes: CHANGELOG.md · Closes #147 via #150