Two back-to-back merges to main cancelled the first merge's deploy: the second
push started a new run in the same concurrency group with cancel-in-progress,
killing the first's Deploy Agent mid-build and leaving the agent un-deployed.
Make cancellation conditional on the event being a pull_request, so stale PR CI
still cancels but main-branch deploys always run to completion.
Refs #118.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>