Tiltmeter 0.2.0

Added

• tiltmeter fix <check-id>: a LangChain Deep Agent adapts the code that reads a drifted
  API in a separate git worktree, shows the diff, and on approval commits, pushes and opens
  a pull request with gh. It needs the new fix extra (pip install "tiltmeter[fix]")
  and ANTHROPIC_API_KEY, and is configured in the new fix section of tiltmeter.yaml.
• A GitHub Action, tiltmeter-dev/tiltmeter-action,
  that keeps the baseline in the Actions cache and reports drift in the job summary.

Changed

• The project homepage is now https://tiltmeter.dev.