feat: 完善使用记录端点可观测性与分布统计

将入站、上游与路径三类端点分布统一到使用记录页的一致化卡片交互中，并补齐端点元数据与统计链路，提升排障与流量分析效率。

backend/internal/handler/dto/mappers.go

@@ -523,6 +523,8 @@ func usageLogFromServiceUser(l *service.UsageLog) UsageLog {
 		Model:                 l.Model,
 		ServiceTier:           l.ServiceTier,
 		ReasoningEffort:       l.ReasoningEffort,
+		InboundEndpoint:       l.InboundEndpoint,
+		UpstreamEndpoint:      l.UpstreamEndpoint,
 		GroupID:               l.GroupID,
 		SubscriptionID:        l.SubscriptionID,
 		InputTokens:           l.InputTokens,

backend/internal/handler/dto/mappers_usage_test.go

@@ -76,10 +76,14 @@ func TestUsageLogFromService_IncludesServiceTierForUserAndAdmin(t *testing.T) {
 	t.Parallel()
 
 	serviceTier := "priority"
+	inboundEndpoint := "/v1/chat/completions"
+	upstreamEndpoint := "/v1/responses"
 	log := &service.UsageLog{
 		RequestID:             "req_3",
 		Model:                 "gpt-5.4",
 		ServiceTier:           &serviceTier,
+		InboundEndpoint:       &inboundEndpoint,
+		UpstreamEndpoint:      &upstreamEndpoint,
 		AccountRateMultiplier: f64Ptr(1.5),
 	}
 
@@ -88,8 +92,16 @@ func TestUsageLogFromService_IncludesServiceTierForUserAndAdmin(t *testing.T) {
 
 	require.NotNil(t, userDTO.ServiceTier)
 	require.Equal(t, serviceTier, *userDTO.ServiceTier)
+	require.NotNil(t, userDTO.InboundEndpoint)
+	require.Equal(t, inboundEndpoint, *userDTO.InboundEndpoint)
+	require.NotNil(t, userDTO.UpstreamEndpoint)
+	require.Equal(t, upstreamEndpoint, *userDTO.UpstreamEndpoint)
 	require.NotNil(t, adminDTO.ServiceTier)
 	require.Equal(t, serviceTier, *adminDTO.ServiceTier)
+	require.NotNil(t, adminDTO.InboundEndpoint)
+	require.Equal(t, inboundEndpoint, *adminDTO.InboundEndpoint)
+	require.NotNil(t, adminDTO.UpstreamEndpoint)
+	require.Equal(t, upstreamEndpoint, *adminDTO.UpstreamEndpoint)
 	require.NotNil(t, adminDTO.AccountRateMultiplier)
 	require.InDelta(t, 1.5, *adminDTO.AccountRateMultiplier, 1e-12)
 }

backend/internal/handler/dto/types.go

@@ -337,6 +337,10 @@ type UsageLog struct {
 	// ReasoningEffort is the request's reasoning effort level (OpenAI Responses API).
 	// nil means not provided / not applicable.
 	ReasoningEffort *string `json:"reasoning_effort,omitempty"`
+	// InboundEndpoint is the client-facing API endpoint path, e.g. /v1/chat/completions.
+	InboundEndpoint *string `json:"inbound_endpoint,omitempty"`
+	// UpstreamEndpoint is the normalized upstream endpoint path, e.g. /v1/responses.
+	UpstreamEndpoint *string `json:"upstream_endpoint,omitempty"`
 
 	GroupID        *int64 `json:"group_id"`
 	SubscriptionID *int64 `json:"subscription_id"`

backend/internal/handler/openai_chat_completions.go

@@ -256,14 +256,16 @@ func (h *OpenAIGatewayHandler) ChatCompletions(c *gin.Context) {
 
 		h.submitUsageRecordTask(func(ctx context.Context) {
 			if err := h.gatewayService.RecordUsage(ctx, &service.OpenAIRecordUsageInput{
-				Result:        result,
-				APIKey:        apiKey,
-				User:          apiKey.User,
-				Account:       account,
-				Subscription:  subscription,
-				UserAgent:     userAgent,
-				IPAddress:     clientIP,
-				APIKeyService: h.apiKeyService,
+				Result:           result,
+				APIKey:           apiKey,
+				User:             apiKey.User,
+				Account:          account,
+				Subscription:     subscription,
+				InboundEndpoint:  normalizedOpenAIInboundEndpoint(c, openAIInboundEndpointChatCompletions),
+				UpstreamEndpoint: normalizedOpenAIUpstreamEndpoint(c, openAIUpstreamEndpointResponses),
+				UserAgent:        userAgent,
+				IPAddress:        clientIP,
+				APIKeyService:    h.apiKeyService,
 			}); err != nil {
 				logger.L().With(
 					zap.String("component", "handler.openai_gateway.chat_completions"),

backend/internal/handler/openai_gateway_endpoint_normalization_test.go

@@ -0,0 +1,57 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+)
+
+func TestNormalizedOpenAIUpstreamEndpoint(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	tests := []struct {
+		name     string
+		path     string
+		fallback string
+		want     string
+	}{
+		{
+			name:     "responses root maps to responses upstream",
+			path:     "/v1/responses",
+			fallback: openAIUpstreamEndpointResponses,
+			want:     "/v1/responses",
+		},
+		{
+			name:     "responses compact keeps compact suffix",
+			path:     "/openai/v1/responses/compact",
+			fallback: openAIUpstreamEndpointResponses,
+			want:     "/v1/responses/compact",
+		},
+		{
+			name:     "responses nested suffix preserved",
+			path:     "/openai/v1/responses/compact/detail",
+			fallback: openAIUpstreamEndpointResponses,
+			want:     "/v1/responses/compact/detail",
+		},
+		{
+			name:     "non responses path uses fallback",
+			path:     "/v1/messages",
+			fallback: openAIUpstreamEndpointResponses,
+			want:     "/v1/responses",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			rec := httptest.NewRecorder()
+			c, _ := gin.CreateTestContext(rec)
+			c.Request = httptest.NewRequest(http.MethodPost, tt.path, nil)
+
+			got := normalizedOpenAIUpstreamEndpoint(c, tt.fallback)
+			require.Equal(t, tt.want, got)
+		})
+	}
+}

backend/internal/handler/openai_gateway_handler.go

@@ -37,6 +37,13 @@ type OpenAIGatewayHandler struct {
 	cfg                     *config.Config
 }
 
+const (
+	openAIInboundEndpointResponses       = "/v1/responses"
+	openAIInboundEndpointMessages        = "/v1/messages"
+	openAIInboundEndpointChatCompletions = "/v1/chat/completions"
+	openAIUpstreamEndpointResponses      = "/v1/responses"
+)
+
 // NewOpenAIGatewayHandler creates a new OpenAIGatewayHandler
 func NewOpenAIGatewayHandler(
 	gatewayService *service.OpenAIGatewayService,
@@ -362,6 +369,8 @@ func (h *OpenAIGatewayHandler) Responses(c *gin.Context) {
 				User:               apiKey.User,
 				Account:            account,
 				Subscription:       subscription,
+				InboundEndpoint:    normalizedOpenAIInboundEndpoint(c, openAIInboundEndpointResponses),
+				UpstreamEndpoint:   normalizedOpenAIUpstreamEndpoint(c, openAIUpstreamEndpointResponses),
 				UserAgent:          userAgent,
 				IPAddress:          clientIP,
 				RequestPayloadHash: requestPayloadHash,
@@ -738,6 +747,8 @@ func (h *OpenAIGatewayHandler) Messages(c *gin.Context) {
 				User:               apiKey.User,
 				Account:            account,
 				Subscription:       subscription,
+				InboundEndpoint:    normalizedOpenAIInboundEndpoint(c, openAIInboundEndpointMessages),
+				UpstreamEndpoint:   normalizedOpenAIUpstreamEndpoint(c, openAIUpstreamEndpointResponses),
 				UserAgent:          userAgent,
 				IPAddress:          clientIP,
 				RequestPayloadHash: requestPayloadHash,
@@ -1235,6 +1246,8 @@ func (h *OpenAIGatewayHandler) ResponsesWebSocket(c *gin.Context) {
 					User:               apiKey.User,
 					Account:            account,
 					Subscription:       subscription,
+					InboundEndpoint:    normalizedOpenAIInboundEndpoint(c, openAIInboundEndpointResponses),
+					UpstreamEndpoint:   normalizedOpenAIUpstreamEndpoint(c, openAIUpstreamEndpointResponses),
 					UserAgent:          userAgent,
 					IPAddress:          clientIP,
 					RequestPayloadHash: service.HashUsageRequestPayload(firstMessage),
@@ -1530,6 +1543,62 @@ func openAIWSIngressFallbackSessionSeed(userID, apiKeyID int64, groupID *int64)
 	return fmt.Sprintf("openai_ws_ingress:%d:%d:%d", gid, userID, apiKeyID)
 }
 
+func normalizedOpenAIInboundEndpoint(c *gin.Context, fallback string) string {
+	path := strings.TrimSpace(fallback)
+	if c != nil {
+		if fullPath := strings.TrimSpace(c.FullPath()); fullPath != "" {
+			path = fullPath
+		} else if c.Request != nil && c.Request.URL != nil {
+			if requestPath := strings.TrimSpace(c.Request.URL.Path); requestPath != "" {
+				path = requestPath
+			}
+		}
+	}
+
+	switch {
+	case strings.Contains(path, openAIInboundEndpointChatCompletions):
+		return openAIInboundEndpointChatCompletions
+	case strings.Contains(path, openAIInboundEndpointMessages):
+		return openAIInboundEndpointMessages
+	case strings.Contains(path, openAIInboundEndpointResponses):
+		return openAIInboundEndpointResponses
+	default:
+		return path
+	}
+}
+
+func normalizedOpenAIUpstreamEndpoint(c *gin.Context, fallback string) string {
+	base := strings.TrimSpace(fallback)
+	if base == "" {
+		base = openAIUpstreamEndpointResponses
+	}
+	base = strings.TrimRight(base, "/")
+
+	if c == nil || c.Request == nil || c.Request.URL == nil {
+		return base
+	}
+
+	path := strings.TrimRight(strings.TrimSpace(c.Request.URL.Path), "/")
+	if path == "" {
+		return base
+	}
+
+	idx := strings.LastIndex(path, "/responses")
+	if idx < 0 {
+		return base
+	}
+
+	suffix := strings.TrimSpace(path[idx+len("/responses"):])
+	if suffix == "" || suffix == "/" {
+		return base
+	}
+	if !strings.HasPrefix(suffix, "/") {
+		return base
+	}
+
+	return base + suffix
+}
+
 func isOpenAIWSUpgradeRequest(r *http.Request) bool {
 	if r == nil {
 		return false