fix(openai): parse nested data usage envelopes

backend/internal/service/openai_gateway_response_handling.go

@@ -979,13 +979,24 @@ func extractOpenAIUsageFromJSONBytes(body []byte) (OpenAIUsage, bool) {
 	if len(body) == 0 || !gjson.ValidBytes(body) {
 		return OpenAIUsage{}, false
 	}
-	if usage, ok := openAIUsageFromGJSON(gjson.GetBytes(body, "usage")); ok {
-		mergeHostedImageGenToolUsage(gjson.GetBytes(body, "tool_usage.image_gen"), &usage)
-		return usage, true
+	// 部分 OpenAI 兼容上游（例如 Cline API）会将标准响应包在 data 字段中：
+	// {"data":{"choices": [...], "usage": {...}}, "success":true}。
+	// 按优先级尝试原生 OpenAI Responses、兼容层 data 包装和 Responses 包装，
+	// 避免同步请求能正常返回但用量被静默记录为 0。
+	candidates := []struct {
+		usagePath      string
+		imageUsagePath string
+	}{
+		{usagePath: "usage", imageUsagePath: "tool_usage.image_gen"},
+		{usagePath: "data.usage", imageUsagePath: "data.tool_usage.image_gen"},
+		{usagePath: "response.usage", imageUsagePath: "response.tool_usage.image_gen"},
+		{usagePath: "data.response.usage", imageUsagePath: "data.response.tool_usage.image_gen"},
 	}
-	if usage, ok := openAIUsageFromGJSON(gjson.GetBytes(body, "response.usage")); ok {
-		mergeHostedImageGenToolUsage(gjson.GetBytes(body, "response.tool_usage.image_gen"), &usage)
-		return usage, true
+	for _, candidate := range candidates {
+		if usage, ok := openAIUsageFromGJSON(gjson.GetBytes(body, candidate.usagePath)); ok {
+			mergeHostedImageGenToolUsage(gjson.GetBytes(body, candidate.imageUsagePath), &usage)
+			return usage, true
+		}
 	}
 	return OpenAIUsage{}, false
 }

backend/internal/service/openai_gateway_service_test.go

@@ -472,6 +472,17 @@ func TestExtractOpenAIUsage_CapturesImageInputTokens(t *testing.T) {
 	require.Zero(t, tu.ImageInputTokens)
 }
 
+func TestExtractOpenAIUsage_ReadsClineDataEnvelope(t *testing.T) {
+	body := []byte(`{"data":{"choices":[{"message":{"content":"OK"}}],"usage":{"prompt_tokens":8,"completion_tokens":27,"total_tokens":35,"prompt_tokens_details":{"cached_tokens":4}}},"success":true}`)
+
+	usage, ok := extractOpenAIUsageFromJSONBytes(body)
+
+	require.True(t, ok)
+	require.Equal(t, 8, usage.InputTokens)
+	require.Equal(t, 27, usage.OutputTokens)
+	require.Equal(t, 4, usage.CacheReadInputTokens)
+}
+
 func TestOpenAIGatewayService_BindHTTPResponseAccount(t *testing.T) {
 	gin.SetMode(gin.TestMode)
 	rec := httptest.NewRecorder()