feat: 算力引擎 Go 后端核心（new-api）

- 统一 OpenAI 兼容 /v1 中继 + 渠道/额度/令牌/流水
- 各领域包：relay 模型网关、model 数据层、controller 管理 API

controller/option_claude_test.go

@@ -0,0 +1,34 @@
+package controller
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/QuantumNous/new-api/common"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestUpdateOptionRejectsNegativeClaudeDefaultMaxTokens(t *testing.T) {
+	response := httptest.NewRecorder()
+	context, _ := gin.CreateTestContext(response)
+	context.Request = httptest.NewRequest(
+		http.MethodPut,
+		"/api/option/",
+		strings.NewReader(`{"key":"claude.default_max_tokens","value":"{\"default\":-1}"}`),
+	)
+
+	UpdateOption(context)
+
+	assert.Equal(t, http.StatusOK, response.Code)
+	var payload struct {
+		Success bool   `json:"success"`
+		Message string `json:"message"`
+	}
+	require.NoError(t, common.Unmarshal(response.Body.Bytes(), &payload))
+	assert.False(t, payload.Success)
+	assert.Contains(t, payload.Message, "-1")
+}