v2.1.0 - complete file operations toolkit New builtin commands: - move-file <src> <dst> - copy-file <src> <dst> - file-info <path> (JSON output) - file-exists <path> (true/false) - file-hash <path> (SHA-256) - disk-usage [path] (bytes) - search-files <glob-pattern> (recursive) - append-file <path> (stdin) All operations sandboxed to /work with full path traversal protection. 27 new integration tests added.