The controller writes no /etc/hosts (hq ADR 0199)

/etc/hosts is the file of the node-hosts-file seat's holder; the controller writes into no file
another seat's holder owns, and asks that holder if it ever needs a line there. The private
network's module stops asking for the node-names fact; every machine already asks the mesh's
one resolver for these names, and the host gives the region back at the next push.

internal/catalogue/provided_test.go

@@ -50,12 +50,14 @@ func TestTheShippedNetworkingModulesResolveOnTheirOwn(t *testing.T) {
 		}
 	}
 
-	// **The names come WITH the network now, not from a third module.** Being on the private
-	// network is what gives a machine a name, so the provider asks for the node-names fact and
-	// there is nothing else to bring in. A module that ran nothing used to be here.
+	// **The network writes no names** (novox/hq ADR 0199): /etc/hosts is the hosts seat holder's
+	// file, and the mesh's resolver answers the machines' names. No fact of the network's module
+	// may name that file.
 	for _, m := range got.Modules {
-		if m.Module == overlay.Name && m.Facts["node-names"].Path == "" {
-			t.Fatalf("the network's provider does not ask for the names: %+v", m.Facts)
+		for name, f := range m.Facts {
+			if m.Module == overlay.Name && f.Path == "/etc/hosts" {
+				t.Fatalf("the network's provider still writes /etc/hosts, as its %q fact", name)
+			}
 		}
 	}
 }