Grant the grants part publishing the modules' memberships, and nothing more (ADR 0547 §5, issue 1945)

No membership is published since release 6 (issue 1945 notes 42, 47), so a seat-holding module placed now cannot
serve its seat or pull asks (mesh-build-go on ace, 2026-10-25). The operator decided at 22:31 that the grants part
publishes them from the first milestone: its principal, module mesh-grants, may publish mesh.assignment.*.* and no
stream definition. The SDK's copy of this composer gets the same line, so the two stay byte-equal.

Research 072 (the controller, NATS-native): this moves the memberships of its Bus row to the grants part.

internal/broker/membership_test.go

@@ -72,6 +72,15 @@ func TestAnAccountMayReadItsOwnMembershipAndNoOthers(t *testing.T) {
 	has(t, perms.Subscribe, "mesh.assignment.anchor.postgres")
 	has(t, perms.Publish, "$JS.API.DIRECT.GET.ASSIGNMENTS.mesh.assignment.anchor.postgres")
 	hasNot(t, perms.Subscribe, "mesh.assignment.>")
+	hasNot(t, perms.Publish, "mesh.assignment.*.*")
+	// The grants part alone publishes memberships (ADR 0547 §5), and defines no stream.
+	grants, err := PermissionsFor(Principal{Kind: KindModule, Node: "anchor", Module: GrantsModule, PasswordHash: "x"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	has(t, grants.Publish, "mesh.assignment.*.*")
+	hasNot(t, grants.Publish, "$JS.API.STREAM.CREATE.>")
+	hasNot(t, grants.Publish, "mesh.assignment.>")
 }
 
 // The runtime arriving on a machine changes nothing about what each module is issued (to-be 38 WP2):

internal/broker/nats.go

@@ -915,6 +915,11 @@ func PermissionsFor(p Principal) (Permissions, error) {
 			sub = append(sub, BusConnectSubject, BusDisconnectSubject)
 			pub = append(pub, BusConnzSubject)
 		}
+		// The grants part alone publishes the modules' memberships into the assignments stream (novox/hq ADR 0547 §5;
+		// the operator, 2026-10-25 22:31): one per subject, `mesh.assignment.<node>.<module>`, and no stream it defines.
+		if p.Module == GrantsModule {
+			pub = append(pub, "mesh.assignment.*.*")
+		}
 		// The view alone reads the build seats' workers for the backlog of asks (issue 1887 A8a).
 		if p.Module == ViewModule {
 			pub = append(pub, BuildBacklogReads()...)
@@ -1581,6 +1586,10 @@ func ComposeAccounts(principals []Principal) (string, error) {
 // from them. No other principal is granted the subjects below, and nothing is a wildcard over them.
 const WatchmanModule = "mesh-delivery-watchman"
 
+// GrantsModule is the one module whose principal publishes the modules' memberships (novox/hq ADR 0547 §5): the grants
+// part, which composes them from the manifests and placement. It defines no stream and is granted no other subject here.
+const GrantsModule = "mesh-grants"
+
 // The bus's own events, imported into MESH from the default system account `$SYS` under subjects of MESH's own
 // (novox/hq ADR 0431 §1, issue 1147): the server says an account's connections opening and closing only to the system
 // account, and the list of an account's connections only to a request made there. `$SYS` holds no user, so nobody