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

relay/channel/openrouter/dto.go

@@ -0,0 +1,17 @@
+package openrouter
+
+import "encoding/json"
+
+type RequestReasoning struct {
+	Enabled bool `json:"enabled"`
+	// One of the following (not both):
+	Effort    string `json:"effort,omitempty"`     // Can be "high", "medium", or "low" (OpenAI-style)
+	MaxTokens int    `json:"max_tokens,omitempty"` // Specific token limit (Anthropic-style)
+	// Optional: Default is false. All models support this.
+	Exclude bool `json:"exclude,omitempty"` // Set to true to exclude reasoning tokens from response
+}
+
+type OpenRouterEnterpriseResponse struct {
+	Data    json.RawMessage `json:"data"`
+	Success bool            `json:"success"`
+}