refactor: 调整 server 目录结构

backend/internal/server/routes/gateway.go

@@ -0,0 +1,30 @@
+package routes
+
+import (
+	"github.com/Wei-Shaw/sub2api/internal/handler"
+	"github.com/Wei-Shaw/sub2api/internal/server/middleware"
+
+	"github.com/gin-gonic/gin"
+)
+
+// RegisterGatewayRoutes 注册 API 网关路由（Claude/OpenAI 兼容）
+func RegisterGatewayRoutes(
+	r *gin.Engine,
+	h *handler.Handlers,
+	apiKeyAuth middleware.ApiKeyAuthMiddleware,
+) {
+	// API网关（Claude API兼容）
+	gateway := r.Group("/v1")
+	gateway.Use(gin.HandlerFunc(apiKeyAuth))
+	{
+		gateway.POST("/messages", h.Gateway.Messages)
+		gateway.POST("/messages/count_tokens", h.Gateway.CountTokens)
+		gateway.GET("/models", h.Gateway.Models)
+		gateway.GET("/usage", h.Gateway.Usage)
+		// OpenAI Responses API
+		gateway.POST("/responses", h.OpenAIGateway.Responses)
+	}
+
+	// OpenAI Responses API（不带v1前缀的别名）
+	r.POST("/responses", gin.HandlerFunc(apiKeyAuth), h.OpenAIGateway.Responses)
+}