Keep what each machine says of what it runs, raise it, and gate on it (hq ADR 0240, to-be 48 Phase A)

The gate judged a module by what the mesh saw from outside, so a container that
crash-looped after it applied passed it. Each machine's node-engine now states
the health of every long-running resource it runs; the controller keeps the
newest statement per machine, raises module.<module>.<machine>.unhealthy on the
second statement in a row, clears it on the first that does not say it, and the
gate passes a module only when every long-running resource of it is stated
healthy since the send. An engine that states nothing is judged as before.

internal/link/contracts_test.go

@@ -16,7 +16,7 @@ import (
 func TestEveryConsumedKindHasAContract(t *testing.T) {
 	// What the controller can be handed, from the subjects it is granted and the ones it derives.
 	subjects := []string{EnrolSubject, BuiltSubject, ReportSubject("anchor"), AliveSubject("anchor"),
-		ToolsAliveSubject("anchor"), "mesh.mod.postgres.event.provisioner.failing"}
+		ToolsAliveSubject("anchor"), HealthSubject("anchor"), "mesh.mod.postgres.event.provisioner.failing"}
 	subjects = append(subjects, broker.ControllerFollows...)
 	kinds := map[string]bool{}
 	for _, s := range subjects {