The controller now decides what a pull request's check runs from the mesh's module
graph, so the announcement carries the changed directories that hold a module at the
head and whether the head has a merge-check.sh. A verdict sets mesh/merge-gate (the
gate, with the modules it judged) and mesh/repo-check (the repository's own tests).
gitea_branch_protection_get/set let the operator's agent make those statuses required.
The catalogue's merge-check.sh leaves the gate to the build seat and keeps its own layer:
every manifest through module check, and the touched Go modules' tests.
The forge's announcer announces each new head of an open pull request as pull.updated, once,
and marks the head pending; the controller asks the build seat to check it against every
machine of the mesh's facts, and says the verdict as checked, which the forge's holder sets as
the head commit's status mesh/merge-gate - an error never as a success - with the check's own
account as a comment when it is not a pass. merge-check.sh is the catalogue's check: every
manifest through the running controller's module check and merge gate, and the Go tests of each
module the change touches, a module whose dependencies cannot be fetched said as not tested.