fix(model): 支持不设置推理强度

internal/backend/server/config/types.go

@@ -141,8 +141,8 @@ func NormalizeModelAdapterConfigs(input []ModelAdapterConfig) ([]ModelAdapterCon
 			return nil, errors.New("模型适配器 tooltipData 不能为空")
 		case next.ModelID == "":
 			return nil, errors.New("模型适配器 modelID 不能为空")
-		case next.Type == "openai" && next.ReasoningEffort == "":
-			return nil, errors.New("模型适配器 reasoningEffort 仅支持 low、medium、high、xhigh、max")
+		case next.Type == "openai" && !isSupportedReasoningEffort(next.ReasoningEffort):
+			return nil, errors.New("模型适配器 reasoningEffort 仅支持空值、low、medium、high、xhigh、max")
 		case next.Type == "openai" && next.OpenAIEndpoint == "":
 			return nil, errors.New("模型适配器 openAIEndpoint 仅支持 /v1/responses、/v1/chat/completions 或 /custom（自定义路径）")
 		case next.Type == "openai" && next.OpenAIExtraParamsEnabled:
@@ -224,13 +224,15 @@ func validateHeadersJSON(value string) error {
 }
 
 func normalizeReasoningEffort(value string) string {
-	switch strings.ToLower(strings.TrimSpace(value)) {
-	case "", "medium":
-		return "medium"
-	case "low", "high", "xhigh", "max":
-		return strings.ToLower(strings.TrimSpace(value))
+	return strings.ToLower(strings.TrimSpace(value))
+}
+
+func isSupportedReasoningEffort(value string) bool {
+	switch value {
+	case "", "low", "medium", "high", "xhigh", "max":
+		return true
 	default:
-		return ""
+		return false
 	}
 }
 

internal/backend/server/config/types_test.go

@@ -58,3 +58,25 @@ func TestNormalizeModelAdapterConfigsUsesStableExplicitSort(t *testing.T) {
 		}
 	}
 }
+
+func TestNormalizeModelAdapterConfigsAllowsBlankReasoningEffort(t *testing.T) {
+	adapter := testModelAdapter("non-reasoning-model", 1)
+	adapter.ReasoningEffort = ""
+
+	adapters, err := NormalizeModelAdapterConfigs([]ModelAdapterConfig{adapter})
+	if err != nil {
+		t.Fatalf("NormalizeModelAdapterConfigs returned error: %v", err)
+	}
+	if got := adapters[0].ReasoningEffort; got != "" {
+		t.Fatalf("ReasoningEffort = %q, want blank", got)
+	}
+}
+
+func TestNormalizeModelAdapterConfigsRejectsUnknownReasoningEffort(t *testing.T) {
+	adapter := testModelAdapter("invalid-reasoning-effort", 1)
+	adapter.ReasoningEffort = "unsupported"
+
+	if _, err := NormalizeModelAdapterConfigs([]ModelAdapterConfig{adapter}); err == nil {
+		t.Fatal("NormalizeModelAdapterConfigs should reject an unknown reasoning effort")
+	}
+}