v2.6.1

Fixed

• CI and Brief now report local HEAD with the latest run per workflow/event; no runs is unknown.
• Complete repo-status-json command documentation and syntax gate; failed collectors always return a nonempty error.
• Ignore machine-specific Claude settings.
• mq-hal repo-status-json --repo <name> is now a real subcommand. It
  was only a prompt intent, so mq-mcp's hal_repo_report mode
  repo-status-json, which passes --repo, exited 2 with
  unrecognized arguments. An unknown repo now exits 2 instead of
  the intent's silent fallback to the default repo, and stdout is pure
  JSON. The prompt intent shares the same builder.
• mq-hal release-brief now fails the release check when the target tag
  already has a GitHub release, and says how many commits have landed
  since. It compared the target with the latest release and called a
  match OK, so a repo whose VERSION was already out read ready and was
  told to publish that tag again. "release not found" is OK; any other
  gh error stays a warning.
• release-check.sh now runs the Python unit tests in tests/test_*.py
  with pytest, one process per file. CI and the release gate never ran
  them before. CI installs pytest alongside jsonschema.