Drift v0.2.3 — Wave-2 Audit Fixes

Fixed

• doctor --fix no longer fails with FOREIGN KEY constraint failed when
  deleting an intent that has children — deleteById now reparents the
  dependants to the deleted intent's parent first (transactional, with
  rollback on error).
• CLI usage errors stay machine-readable under --json — an empty prompt
  (-p "") or missing arguments previously printed plain-text usage to
  stdout, which broke MCP tool callers. They now emit
  { "status": "error", "type", "message", "exitCode" } like every other
  failure.
• drift blame / drift context reject paths that escape the repository
  root — ../ traversal, absolute and cross-drive paths (and symlinks
  escaping the repo, via realpath) are rejected with a clean error before
  any filesystem read. Previously blame read the file first, leaking
  absolute paths in error messages and probing arbitrary files.

Tests

81 passing tests (was 77): +4 — deleteById reparenting (FK no longer fails),
the MCP JSON error contract (empty prompt / unknown intent), and path
containment coverage (absolute path, ../ traversal, --function, context).