feat(platform): summarize service status on dashboard

vehicle-data-platform/apps/api/internal/platform/handler_test.go

@@ -19,6 +19,9 @@ func TestHandlerDashboardSummary(t *testing.T) {
 	if !strings.Contains(rec.Body.String(), "onlineVehicles") {
 		t.Fatalf("response missing onlineVehicles: %s", rec.Body.String())
 	}
+	if !strings.Contains(rec.Body.String(), "serviceStatuses") || !strings.Contains(rec.Body.String(), "degraded") {
+		t.Fatalf("response missing vehicle service status distribution: %s", rec.Body.String())
+	}
 }
 
 func TestHandlerVehicles(t *testing.T) {

vehicle-data-platform/apps/api/internal/platform/mock_store.go

@@ -44,6 +44,12 @@ func (m *MockStore) DashboardSummary(context.Context) (DashboardSummary, error)
 			{Protocol: "JT808", Online: 73, Total: 318},
 			{Protocol: "YUTONG_MQTT", Online: 1, Total: 8},
 		},
+		ServiceStatuses: []ServiceStatusStat{
+			{Status: "healthy", Title: "服务正常", Count: 2},
+			{Status: "degraded", Title: "部分来源离线", Count: 1},
+			{Status: "offline", Title: "车辆离线", Count: 1},
+			{Status: "identity_required", Title: "身份未绑定", Count: 0},
+		},
 		LinkHealth: []LinkHealth{
 			{Name: "Redis realtime", Status: "ok", Detail: "在线状态 1 分钟 TTL 正常"},
 			{Name: "TDengine raw_frames", Status: "ok", Detail: "最近 5 分钟有写入"},

vehicle-data-platform/apps/api/internal/platform/model.go

@@ -8,13 +8,14 @@ type Page[T any] struct {
 }
 
 type DashboardSummary struct {
-	OnlineVehicles int            `json:"onlineVehicles"`
-	ActiveToday    int            `json:"activeToday"`
-	FrameToday     int            `json:"frameToday"`
-	IssueVehicles  int            `json:"issueVehicles"`
-	KafkaLag       *int           `json:"kafkaLag"`
-	Protocols      []ProtocolStat `json:"protocols"`
-	LinkHealth     []LinkHealth   `json:"linkHealth"`
+	OnlineVehicles  int                 `json:"onlineVehicles"`
+	ActiveToday     int                 `json:"activeToday"`
+	FrameToday      int                 `json:"frameToday"`
+	IssueVehicles   int                 `json:"issueVehicles"`
+	KafkaLag        *int                `json:"kafkaLag"`
+	Protocols       []ProtocolStat      `json:"protocols"`
+	ServiceStatuses []ServiceStatusStat `json:"serviceStatuses"`
+	LinkHealth      []LinkHealth        `json:"linkHealth"`
 }
 
 type ProtocolStat struct {
@@ -23,6 +24,12 @@ type ProtocolStat struct {
 	Total    int    `json:"total"`
 }
 
+type ServiceStatusStat struct {
+	Status string `json:"status"`
+	Title  string `json:"title"`
+	Count  int    `json:"count"`
+}
+
 type LinkHealth struct {
 	Name   string `json:"name"`
 	Status string `json:"status"`

vehicle-data-platform/apps/api/internal/platform/production_store.go

@@ -60,6 +60,11 @@ func (s *ProductionStore) DashboardSummary(ctx context.Context) (DashboardSummar
 		return DashboardSummary{}, err
 	}
 	summary.Protocols = protocols
+	serviceStatuses, err := s.serviceStatusStats(ctx)
+	if err != nil {
+		return DashboardSummary{}, err
+	}
+	summary.ServiceStatuses = serviceStatuses
 	health, err := s.OpsHealth(ctx)
 	if err != nil {
 		return DashboardSummary{}, err
@@ -69,6 +74,27 @@ func (s *ProductionStore) DashboardSummary(ctx context.Context) (DashboardSummar
 	return summary, nil
 }
 
+func (s *ProductionStore) serviceStatusStats(ctx context.Context) ([]ServiceStatusStat, error) {
+	definitions := []ServiceStatusStat{
+		{Status: "healthy", Title: "服务正常"},
+		{Status: "degraded", Title: "部分来源离线"},
+		{Status: "offline", Title: "车辆离线"},
+		{Status: "identity_required", Title: "身份未绑定"},
+	}
+	out := make([]ServiceStatusStat, 0, len(definitions))
+	for _, definition := range definitions {
+		query := url.Values{"serviceStatus": {definition.Status}, "limit": {"1"}}
+		built := buildVehicleCoverageSQL(query)
+		count := 0
+		if err := s.db.QueryRowContext(ctx, built.CountText, built.CountArgs...).Scan(&count); err != nil {
+			return nil, err
+		}
+		definition.Count = count
+		out = append(out, definition)
+	}
+	return out, nil
+}
+
 func (s *ProductionStore) frameToday(ctx context.Context, now time.Time) (int, error) {
 	if s.tdengine == nil {
 		return 0, nil