Development Plan: superseded runs are cancelled by CI now

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPQ14L3LikyefCMFBqEbKE

docs/Development-Plan.md

@@ -81,8 +81,8 @@ Only `nisse-dev` has real code; `nisse-core` and `nisse-ops` are placeholders.
   runs that full set before its image is built. The end-to-end tests drive the
   real agent, every role on a local model (so they cost nothing per call), in a
   repository of the run's own, with a scripted operator; CI runs them after the
-  checks pass. There is one runner, and a run a newer push
-  supersedes has to be cancelled by hand. Locally only the tests being written
+  checks pass. There is one runner, so a newer run for a
+  PR or branch cancels the one it supersedes (#126). Locally only the tests being written
   (`-k`) or diagnosed (`--lf`); `scripts/e2e.sh` reports what a run spent. Manual
   live runs are for the new loop's first runs and phase ends. Findings are filed as
   issues and either fixed before moving on or deliberately deferred.