ax(node): complete HandleGetStats test triple with Bad and Ugly cases

TestWorker_HandleGetStats_Bad and TestWorker_HandleGetStats_Ugly were
missing; AX requires all three categories mandatory per function.
Bad covers uninitialised identity, Ugly covers failed miner stat collection.

Co-Authored-By: Charon <charon@lethean.io>

pkg/node/worker_test.go

@@ -308,6 +308,90 @@ func TestWorker_HandleGetStats_Good(t *testing.T) {
 	}
 }
 
+func TestWorker_HandleGetStats_Bad(t *testing.T) {
+	tmpDir := t.TempDir()
+	// Identity deliberately not generated — worker must return error
+	nodeManager, err := NewNodeManagerWithPaths(
+		tmpDir+"/private.key",
+		tmpDir+"/node.json",
+	)
+	if err != nil {
+		t.Fatalf("failed to create node manager: %v", err)
+	}
+
+	peerRegistry, err := NewPeerRegistryWithPath(t.TempDir() + "/peers.json")
+	if err != nil {
+		t.Fatalf("failed to create peer registry: %v", err)
+	}
+
+	transport := NewTransport(nodeManager, peerRegistry, DefaultTransportConfig())
+	worker := NewWorker(nodeManager, transport)
+
+	msg, err := NewMessage(MsgGetStats, "sender-id", "uninitialised-id", nil)
+	if err != nil {
+		t.Fatalf("failed to create get_stats message: %v", err)
+	}
+
+	_, err = worker.handleGetStats(msg)
+	if err == nil {
+		t.Error("expected error when node identity is not initialised")
+	}
+}
+
+func TestWorker_HandleGetStats_Ugly(t *testing.T) {
+	tmpDir := t.TempDir()
+	nodeManager, err := NewNodeManagerWithPaths(
+		tmpDir+"/private.key",
+		tmpDir+"/node.json",
+	)
+	if err != nil {
+		t.Fatalf("failed to create node manager: %v", err)
+	}
+	if err := nodeManager.GenerateIdentity("test-worker", RoleWorker); err != nil {
+		t.Fatalf("failed to generate identity: %v", err)
+	}
+
+	peerRegistry, err := NewPeerRegistryWithPath(t.TempDir() + "/peers.json")
+	if err != nil {
+		t.Fatalf("failed to create peer registry: %v", err)
+	}
+
+	transport := NewTransport(nodeManager, peerRegistry, DefaultTransportConfig())
+	worker := NewWorker(nodeManager, transport)
+
+	// Miner manager returns stats errors — handleGetStats must skip failed miners and still succeed
+	failingManager := &mockMinerManager{
+		miners: []MinerInstance{&mockFailingMinerInstance{name: "broken", minerType: "xmrig"}},
+	}
+	worker.SetMinerManager(failingManager)
+
+	identity := nodeManager.GetIdentity()
+	if identity == nil {
+		t.Fatal("expected identity to be generated")
+	}
+	msg, err := NewMessage(MsgGetStats, "sender-id", identity.ID, nil)
+	if err != nil {
+		t.Fatalf("failed to create get_stats message: %v", err)
+	}
+
+	response, err := worker.handleGetStats(msg)
+	if err != nil {
+		t.Fatalf("handleGetStats should not fail when a miner stat fetch fails: %v", err)
+	}
+	if response == nil {
+		t.Fatal("expected a response even when miner stats fail")
+	}
+
+	var stats StatsPayload
+	if err := response.ParsePayload(&stats); err != nil {
+		t.Fatalf("failed to parse stats payload: %v", err)
+	}
+	// Broken miner is skipped — miners list is empty
+	if len(stats.Miners) != 0 {
+		t.Errorf("expected 0 miners (failed stat skipped), got %d", len(stats.Miners))
+	}
+}
+
 func TestWorker_HandleStartMiner_Bad(t *testing.T) {
 	cleanup := setupTestEnv(t)
 	defer cleanup()
@@ -588,6 +672,18 @@ func (m *mockMinerInstance) GetType() string                      { return m.min
 func (m *mockMinerInstance) GetStats() (interface{}, error)       { return m.stats, nil }
 func (m *mockMinerInstance) GetConsoleHistory(lines int) []string { return []string{} }
 
+type mockFailingMinerInstance struct {
+	name      string
+	minerType string
+}
+
+func (m *mockFailingMinerInstance) GetName() string { return m.name }
+func (m *mockFailingMinerInstance) GetType() string { return m.minerType }
+func (m *mockFailingMinerInstance) GetStats() (interface{}, error) {
+	return nil, &ProtocolError{Code: ErrCodeOperationFailed, Message: "stats unavailable"}
+}
+func (m *mockFailingMinerInstance) GetConsoleHistory(lines int) []string { return []string{} }
+
 type mockProfileManager struct{}
 
 func (m *mockProfileManager) GetProfile(id string) (interface{}, error) {