v0.2.1 - Hardened Security & Edge-Case Defenses

Hardened Security & Robustness in v0.2.1

• Special Device Node Defense:
  • Full support for /dev/null as an empty file operand (--- /dev/null / +++ /dev/null), enabling standard creation/deletion patch workflows.
  • Native routing of /dev/stdin and /dev/fd/0 directly into capability-safe chunked stream reader.
• Symlink Cycle Defense:
  • Implemented ancestor path segment pruning (path_has_segment) and recursion depth bounding (max depth 32) in directory trees (-r).
  • Circular symlinks (e.g. ln -s . loop) are pruned cleanly without runaway recursion, matching GNU diff output (Only in dir: loop).
• Memory & OOM Guard:
  • Added a 100MB file size ceiling guard to prevent out-of-memory exhaustion on pathological huge files.
• Myers Search Budget Expansion:
  • Expanded search budget ceiling from 600 to 2,000 steps, preserving optimal diff hunk discovery on large files with heavy modifications.
• Automated CI/CD:
  • Added GitHub Actions workflow (.github/workflows/ci.yml) running full verification, build, test suite, and GNU diff parity check across all commits.