fix(billing): 修正模型计费配置继承优先级

apps/api/internal/httpapi/model_response_test.go

@@ -173,6 +173,41 @@ func TestPlatformModelResponsePreservesTextGenerateFieldsOverFallbacks(t *testin
 	assertStringListValue(t, textGenerate["thinkingEffortLevels"], []string{"minimal", "low", "medium"})
 }
 
+func TestPlatformModelResponseUsesBaseBillingConfigWithoutMaterializedSnapshot(t *testing.T) {
+	model := store.PlatformModel{
+		ModelName: "base-priced-model",
+		ModelType: store.StringList{"video_generate"},
+		BaseBillingConfig: map[string]any{
+			"video": map[string]any{"basePrice": float64(416)},
+		},
+	}
+
+	response := (&Server{}).platformModelResponse(context.Background(), model)
+	video, ok := response.BillingConfig["video"].(map[string]any)
+	if !ok || video["basePrice"] != float64(416) {
+		t.Fatalf("expected base billing price 416, got %#v", response.BillingConfig)
+	}
+}
+
+func TestEffectiveResponseBillingConfigPrefersBaseRuleOverLegacySnapshot(t *testing.T) {
+	model := store.PlatformModel{
+		BasePricingRuleSetID: "seedance-pricing",
+		BillingConfig: map[string]any{
+			"video": map[string]any{"basePrice": float64(100)},
+		},
+	}
+	response := withEffectiveResponseBillingConfig(model, map[string]map[string]any{
+		"seedance-pricing": {
+			"video": map[string]any{"basePrice": float64(416)},
+		},
+	})
+
+	video, ok := response.BillingConfig["video"].(map[string]any)
+	if !ok || video["basePrice"] != float64(416) {
+		t.Fatalf("expected base rule price 416, got %#v", response.BillingConfig)
+	}
+}
+
 func textGenerateCapabilities(t *testing.T, model store.PlatformModel) map[string]any {
 	t.Helper()
 	capabilities, ok := model.Capabilities["text_generate"].(map[string]any)