v0.2.4

Fixed

• Ctrl-C outside --apply (for example during a live scan, a dry run or groups diff) now prints
  Interrupted. Nothing was changed. and exits 130 instead of showing a traceback. Ctrl-C during
  --apply is unchanged: it is logged and exits 1.
• A groups diff file that is not valid JSON, not UTF-8, or not the shape groups export writes
  (for example a list, a string or a missing groups mapping) now gives
  error: <path>: not a valid groups export: ... and exits 1. The file name is terminal-safe.
• The test suite passes mypy: the untyped cmarkgfm import is marked and a test table is annotated.

Changed

• Docs: README theme and CONTRIBUTING update (#10); the two README roadmap paragraphs are merged
  and the exit code table lists 130.

Security

• CI: Dependabot config for pip and GitHub Actions (#7).
• CI: actions/checkout bumped to 7.0.1 (#9) and actions/setup-python to 7.0.0 (#8), both
  pinned by commit SHA.
• CI: persist-credentials: false on checkout, so the job token is not left in the git config (#11).

Open follow-up

• Add a mypy step to .github/workflows/ci.yml so type errors cannot return. Owner: Grok Bot (needs a workflow-scope change).