Set up Claude Code environment for the MDPI manuscript ...

- Add CLAUDE.md documenting project context, source-material timeline
  and caveats, manuscript structure, and Windows/WSL/macOS environment
  notes.
- Add references.bib stub seeded with cite keys from the MIDL paper.
- Untrack *:Zone.Identifier marker files and ignore them going forward,
  along with common LaTeX build artifacts.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>