v0.2.0

Fixed

• Multi-leg connections are checked in code. A leg must depart at least 45 minutes after
  the trip's previous leg is scheduled to arrive. The approval gate refuses a leg that does not
  connect before you are asked to approve it, and dispatch_flight enforces the same rule. In
  a live test the dispatcher had proposed a second leg that left before the first one landed.
• The approval prompt shows the departure time. Every dispatch now carries its departure
  time. The prompt shows it in the origin's local time and in UTC and, for a later leg, the
  connection after the previous leg arrives (for example "Connection: 5 h 08 min after leg 1
  arrives"). Before, an airline leg's approval had no time on it.

Added

• Version tracking: this changelog, version in the /health response, and Release workflow
  checks that refuse to re-release an existing version or ship one without a changelog entry.
  Each release creates its Git tag and GitHub Release and names the Worker version after it.

Changed

• dispatch_flight requires departure_utc for airline flights as well as private ones
  (the occurrence's scheduled departure from the flight search).
• The README is reorganized for new users and contributors.