Compose the bus's users without the controller, and grant the removal of its leftovers

The controller ended by its unassignment (ADR 0590): its user, its lease's cut and reads, the
operator's hand path to its compositions and its writers' rows go; an enrolling node enrols
through mesh-enrolment alone; the desk's prompt stays the vault's alone (DeskOnly). The golden
lists are now this composer's own, taken first from the controller's with its user removed.
The bus module's tools may remove the controller's leftovers by name, consumers, CONTROL,
ASSIGNMENTS, its 17 buckets and each node's declaration files' bucket, under the word
controller-leftovers (clause 6). The provisioner client reads placement in place of the
assignments mirror. Issue 1126 B3a, B5.

Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL

go/buscompose/engine.go

@@ -74,11 +74,9 @@ func engineGrants(p Principal) (pub, sub []string) {
 	if own, err := NodeKeysGrants(EngineDataBucket, p.Node); err == nil {
 		pub = append(pub, own...)
 	}
-	// And its node's declared packages, its own key alone (ADR 0565 clause 6); and, read, the controller's mirror's key
-	// of its node, which the node seat's verb packages compares it with until the lease write ends the mirror.
+	// And its node's declared packages, its own key alone (ADR 0565 clause 6).
 	if safeSubject.MatchString(p.Node) {
 		pub = append(pub, EnginePackagesGrants(p.Node)...)
-		pub = append(pub, readGrants(DeclaredPackagesBucket, p.Node)...)
 	}
 	return append(pub, tp...), append(sub, ts...)
 }