feat: Implement initial Go backend HTTP API server for Codex Pool, handling configuration, logging, S2A, mail, and team management, and ignore its executable.

.gitignore

@@ -98,3 +98,5 @@ check_ban.py
 .kiro/specs/codex-pool-frontend/design.md
 .kiro/specs/codex-pool-frontend/requirements.md
 .kiro/specs/codex-pool-frontend/tasks.md
+backend/codex-pool.exe
+backend/codex-pool.exe

backend/cmd/main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"encoding/json"
 	"fmt"
+	"net"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -122,7 +123,12 @@ func startServer(cfg *config.Config) {
 	}
 
 	addr := fmt.Sprintf(":%d", cfg.Port)
-	fmt.Printf("[服务] 启动于 http://localhost%s\n", addr)
+	// 显示访问地址
+	fmt.Println("[服务] 启动于:")
+	fmt.Printf("       - 本地: http://localhost:%d\n", cfg.Port)
+	if ip := getOutboundIP(); ip != "" {
+		fmt.Printf("       - 外部: http://%s:%d\n", ip, cfg.Port)
+	}
 	fmt.Println()
 
 	if err := http.ListenAndServe(addr, mux); err != nil {
@@ -349,3 +355,28 @@ func handleRegisterTest(w http.ResponseWriter, r *http.Request) {
 		"access_token": reg.AccessToken,
 	})
 }
+
+// getOutboundIP 获取本机出口 IP
+func getOutboundIP() string {
+	// 方法1: 通过连接获取
+	conn, err := net.Dial("udp", "8.8.8.8:80")
+	if err == nil {
+		defer conn.Close()
+		localAddr := conn.LocalAddr().(*net.UDPAddr)
+		return localAddr.IP.String()
+	}
+
+	// 方法2: 遍历网卡
+	addrs, err := net.InterfaceAddrs()
+	if err != nil {
+		return ""
+	}
+	for _, addr := range addrs {
+		if ipnet, ok := addr.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
+			if ipnet.IP.To4() != nil {
+				return ipnet.IP.String()
+			}
+		}
+	}
+	return ""
+}