Serve the read verbs on the serving controller's own connection, and name every connection

Each verb ran as a process that dialled the bus, so hundreds of short
connections an hour, all named mesh-controller, hid any client reconnecting
in a loop (hq issue 327). D15 now says a user whose connections keep dropping.

cmd/mesh-controller/main.go

@@ -15,6 +15,7 @@ import (
 	"os/signal"
 	"syscall"
 
+	"github.com/novox/mesh-controller/internal/broker"
 	"github.com/novox/mesh-controller/internal/identity"
 	"github.com/novox/mesh-controller/internal/inventory"
 	"github.com/novox/mesh-controller/internal/licences"
@@ -53,6 +54,9 @@ func run() error {
 		return fmt.Errorf("no command given")
 	}
 
+	// Every connection this process dials says what it is (novox/hq issue 327).
+	broker.ConnectionName = connectionName(args[0], os.Getenv(verbVar))
+
 	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
 	defer stop()
 	// Whatever this process holds of the controller's lease is given back as it ends (novox/hq to-be
@@ -416,3 +420,18 @@ func (b builds) Built(ctx context.Context, result link.BuildResult) error {
 	statusFrom.nudge()
 	return nil
 }
+
+// verbVar carries the seat verb a command runs for, from the serving controller to the process it starts.
+const verbVar = "MESH_VERB"
+
+// connectionName is what this process's connections say they are in the bus's list (novox/hq issue 327):
+// the serving controller, a verb's own process and which verb, or a command run at a shell and which.
+func connectionName(command, verb string) string {
+	switch {
+	case command == "serve":
+		return "mesh-controller serving"
+	case verb != "":
+		return "mesh-controller verb " + verb
+	}
+	return "mesh-controller command " + command
+}