One bus: the AMQP transport is gone from the controller

The mesh runs on the seat's bus alone (novox/hq ADR 0131, design 28 task 5.5). The old
transport's consume loop, build request, tool ask, management API and account scoping are
deleted, and the bus switch with them; the controller connects to the broker seat and to
nothing else. The store-window tests keep their assertions on a bus-less fake, and the tests
that only made sense for the old transport's in-memory holding go with it.

internal/link/report_retry_test.go

@@ -46,24 +46,6 @@ func TestAReportTheStoreCouldNotTakeIsHeldAndOneItRefusedIsNot(t *testing.T) {
 	}
 }
 
-// A newer report from the same node supersedes one of its reports still held: recorded after the
-// newer, the older would overwrite what the node is doing now.
-func TestANewerReportSupersedesAHeldOneFromTheSameNode(t *testing.T) {
-	s, in := serving()
-	s.listener = heardWith{err: errors.Join(ErrTryAgain, errors.New("starting up"))}
-	older, newer, other := &settled{}, &settled{}, &settled{}
-	s.act(context.Background(), in.sends(t, older, KindReport, aReport("anchor", "d1")))
-	s.act(context.Background(), in.sends(t, other, KindReport, aReport("laptop", "d7")))
-	s.act(context.Background(), in.sends(t, newer, KindReport, aReport("anchor", "d2")))
-	if !older.acked {
-		t.Fatalf("the older report was not set aside by the newer: %+v", older)
-	}
-	if !newer.unsettled() || !other.unsettled() || len(in.held) != 2 {
-		t.Fatalf("the newer report and another node's were not both held: newer %+v other %+v, %d held",
-			newer, other, len(in.held))
-	}
-}
-
 // A store that has not come back within the bound is not restarting: the report is let go, loudly,
 // rather than held for ever.
 func TestAReportIsLetGoOnceTheStoreHasBeenGoneTooLong(t *testing.T) {