A store row keeps its seat's protocol, and a holder may take work from its queue

The seat table has name, scope, delivers and decision, and the protocol ADR 0129
gave a seat lives only in the compiled defaults; loading the rows dropped it, so
no role's work queue was ever raised and the first build submitted over the new
bus met "no response from stream". Until the table gains the columns, a row with
no protocol keeps the compiled one of its name. And the holder of a seat is
granted what taking work from its queue needs — asking about the worker consumer
it binds, and acknowledging on it — which the first machine to try was refused.

The control plane's own seat placeholders no longer include the old bus's port,
which the switch removed with the variable.

internal/catalogue/holdings_test.go

@@ -143,3 +143,18 @@ func TestAMembershipForTheNewBusIsComposedAsASealedFile(t *testing.T) {
 		}
 	}
 }
+
+// The store's seat rows have no protocol columns yet; loading them must not drop the protocol the
+// bus is derived from, or no role's work queue is ever raised (found live, 2026-09-28).
+func TestAStoreRowWithoutAProtocolKeepsTheCompiledOne(t *testing.T) {
+	was := Seats()
+	t.Cleanup(func() { UseSeats(was) })
+	UseSeats([]Seat{{Name: "mesh-build-machine", Scope: ScopeMesh, Decision: "row"}})
+	got, ok := SeatNamed("mesh-build-machine")
+	if !ok || len(got.Accepts) == 0 {
+		t.Fatalf("the build machine's seat lost what it accepts when loaded from the store: %+v", got)
+	}
+	if got.Decision != "row" {
+		t.Fatalf("the store's own columns were not kept: %+v", got)
+	}
+}