dsh-file-claim: File Claim and Protection for Concurrent DSH Sessions

dsh-file-claim is a DeepSeek Harness (DSH) plugin designed to resolve file conflicts and overwriting issues when multiple concurrent sessions edit the same workspace. Maintained by Nwflower and licensed under MIT, the plugin is zero-dependency and build-free, relying solely on Node.js built-in modules and Git. Its core features include: 1. **File Ownership Management**: Provides `claim_files` and `release_files` tools for exclusive ownership declaration and release of files/directories, supporting idempotent merging and directory-level overrides. 2. **Heartbeat and Takeover Mechanism**: Automatically refreshes heartbeats and cleans up stale ownership of crashed sessions via DSH lifecycle events, with support for `stale`