Merge pull request 'The seat declares the facts its holder states' (#131) from fix/the-seat-declares-the-facts-its-holder-states into main

internal/broker/states_agreement_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/catalogue"
 	"github.com/novox/mesh-controller/internal/link"
 )
 
@@ -27,4 +28,17 @@ func TestTheFactsTheGrantPermitsAreTheFactsTheMeshStates(t *testing.T) {
 	if len(broker.ControllerStates) != 3 {
 		t.Errorf("the grant permits %v, which is more than the mesh states", broker.ControllerStates)
 	}
+	// **And the seat says it.** A seat carries the protocol of its role (novox/hq ADR 0129), so the
+	// facts the control plane states are the seat's `emits` — which is what lets anything else declare
+	// that it consumes them, and what the subject-agreement check reads to know they have an owner.
+	var declared []string
+	for _, seat := range catalogue.SeatsWithAProtocol() {
+		if seat.Name == broker.ControllerSeat {
+			declared = seat.Emits
+		}
+	}
+	if !slices.Equal(declared, broker.ControllerStates) {
+		t.Errorf("the %s seat emits %v and the grant permits %v", broker.ControllerSeat,
+			declared, broker.ControllerStates)
+	}
 }

internal/catalogue/seats.go

@@ -48,7 +48,11 @@ type Seat struct {
 //
 // In the order a person reads it: the mesh's own, then a node's.
 var defaultSeats = []Seat{
-	{Name: "mesh-controller", Scope: ScopeMesh, Decision: "novox/hq ADR 0079"},
+	// The control plane states what it did under the seat it holds (novox/hq ADR 0134): a role's
+	// events belong to the role, so they keep their address while the holder is replaced. No accepts,
+	// so no work queue is raised for it — only what its holder may say.
+	{Name: "mesh-controller", Scope: ScopeMesh, Decision: "novox/hq ADR 0079",
+		Emits: []string{"applied", "refused", "built-before"}},
 	{Name: "mesh-store", Scope: ScopeMesh, Delivers: "postgres-database", Decision: "novox/hq ADR 0079"},
 	// **Delivers the mesh's own bus, not `amqp`.** Those were the same word until
 	// ADR 0127 separated them: `amqp` is a backing service a module may require, and this seat is