Read how a module says each resource is ready, and send it to engines that read it (hq ADR 0240, to-be 48 Phase B)

A module could say nothing about what ready means for what it runs, so a web
application with its port open and its requests hanging passed everything for
eleven hours (issue 145). A long-running resource now carries `health` — the
image's own check adopted by name, http, tcp, exec, unit or a module's own tool,
with its timing — refused near its author when it names a port or an address,
an endpoint the module does not declare, a tool it does not serve, a tool check
alone, or a timing outside the record's bounds. It is composed with the endpoint
as the port this machine published it on, and sent only to a node-engine whose
statement says it reads it: an older one would refuse the whole declaration.
The engine is granted its own machine's instance of each health tool. `module
check` warns of every long-running resource without `health`, counts them for
the catalogue, and refuses them from 2026-11-18. A check's findings stay out of
a condition's summary. The node-engine's validator is vendored at its Phase B
commit, so what is composed is judged by the words the engine takes.

cmd/mesh-controller/module_health_test.go

@@ -161,3 +161,36 @@ func TestAReportWithNoHealthRaisesAndKeepsNothing(t *testing.T) {
 		t.Fatalf("the report's health was not kept: %+v %v %v", kept, had, err)
 	}
 }
+
+// A declared `health` is sent only to an engine whose own statement says it reads it (novox/hq ADR 0240
+// Phase B): an older engine is strict and would refuse the whole declaration for the field.
+func TestHealthIsSentOnlyToAnEngineThatSaysItReadsIt(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	reads := func() bool {
+		t.Helper()
+		got, err := engineReadsHealth(ctx, inv, "anchor")
+		if err != nil {
+			t.Fatal(err)
+		}
+		return got
+	}
+	if reads() {
+		t.Fatal("an engine that never stated anything is sent health")
+	}
+	if err := stateHealth(ctx, inv, nil, "anchor", aStatement(h0, link.StateHealthy), h0); err != nil {
+		t.Fatal(err)
+	}
+	if reads() {
+		t.Fatal("an engine judging liveness alone is sent health")
+	}
+	later := aStatement(h0.Add(time.Minute), link.StateHealthy)
+	later.Contract = link.ReadinessContract
+	if err := stateHealth(ctx, inv, nil, "anchor", later, h0.Add(time.Minute)); err != nil {
+		t.Fatal(err)
+	}
+	if !reads() {
+		t.Fatal("an engine that reads health is not sent it")
+	}
+}