A start writes the pipeline's key (watched branch, source revision, module) only when it is absent and says
pipeline-started; a second start of the same revision and module writes nothing. A package-published asks the
catalog's outdated for that package on that branch, a kept call, and starts a pipeline for each dependent behind
by kind 1, keyed by the publication's branch and source revision. The start on take-in.taken, and a gathered
group's one pipeline per branch, wait for take-in.taken's body (design 47 G §476, in review).
Builds: design 47 G §54, §103, §334, §53, §75
Claude-Session: https://claude.ai/code/session_01JG73KEq4zoDfM9WtYpcQgZ