process: a bucket missing at a part's start is bound when the bus says it was created, keeping what was written meanwhile; buscompose grants each principal the creation of the buckets it may bind (issue 1790)

Since the grants part creates a manifest's buckets after a delivery (ADR 0547), a module restarted by that
delivery can open a new state before it exists; OptionalBucket answered nil and the part never looked again
(mesh-delivery's checker and builder, state hearing, 2026-10-26). AwaitBucket binds on the server's
STREAM.CREATED advisory, or at the next use, and writes the latest value kept per key. The copied composer's
agreement test leaves that one row out: the controller's list is no longer loaded since the take-over.

go/buscompose/buscompose_test.go

@@ -5,6 +5,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"regexp"
 	"strings"
 	"testing"
 )
@@ -14,6 +15,9 @@ import (
 // internal/broker (mesh-controller branch fix/1945-mesh-grants-publishes-memberships, and fix/1790-grants-create-buckets for the grants part creating declared streams), lists and memberships, from fixtures_test.go compiled there unchanged; composed.conf is the
 // controller's golden of the whole server configuration. A row that differs is the copy drifting from the controller,
 // which is a fault while both compose (until the controller loses its lease, ADR 0547 §13).
+// createdAdvisory is one subscription to a bucket's creation in a composed list, as stateCreatedHeard composes it.
+var createdAdvisory = regexp.MustCompile(`"\$JS\.EVENT\.ADVISORY\.STREAM\.CREATED\.KV_[^"]*", `)
+
 func TestTheCopiedComposerComposesAsTheControllers(t *testing.T) {
 	raw, err := os.ReadFile(filepath.Join("testdata", "controller-user-lists.json"))
 	if err != nil {
@@ -48,6 +52,11 @@ func TestTheCopiedComposerComposesAsTheControllers(t *testing.T) {
 			if strings.Join(missing, ",") != strings.Join(want[i].Missing, ",") {
 				t.Errorf("left out %v, the controller %v", missing, want[i].Missing)
 			}
+			// The one row the copy composes beyond the controller's, on purpose (novox/hq issue 1790, 2026-10-26, after
+			// the take-over of ADR 0547 milestone 2): each principal hears its own and read buckets created, so a state
+			// missing at its start is bound when it appears. The controller's composer is frozen and its list no longer
+			// loaded; while it is not, this row is left out of the comparison and nothing else.
+			list = createdAdvisory.ReplaceAllString(list, "")
 			if list != want[i].List {
 				t.Errorf("the list differs from the controller's:\n%s", list)
 			}