Add federation worker and canonical handoffs

internal/herdr/herdr_test.go

@@ -89,6 +89,17 @@ func TestAgentNameIsBoundedAndValid(t *testing.T) {
 	}
 }
 
+func TestAgentNameLongIDsDoNotCollide(t *testing.T) {
+	first := agentName("claude", "task-with-a-very-long-shared-prefix-aaaaaaaa")
+	second := agentName("claude", "task-with-a-very-long-shared-prefix-bbbbbbbb")
+	if first == second {
+		t.Fatalf("long task IDs collided: %q", first)
+	}
+	if len(first) > 32 || len(second) > 32 {
+		t.Fatalf("agent name exceeds limit: %q / %q", first, second)
+	}
+}
+
 func TestPromptDoesNotRetryAmbiguousDelivery(t *testing.T) {
 	ln, err := net.Listen("tcp", "127.0.0.1:0")
 	if err != nil {