feat: Implement initial backend API server with configuration, S2A proxy, and data management, and add frontend Toast component and Config page.

backend/cmd/main.go

@@ -217,6 +217,8 @@ func handleConfig(w http.ResponseWriter, r *http.Request) {
 			"group_ids":           config.Global.GroupIDs,
 			"proxy_enabled":       config.Global.ProxyEnabled,
 			"default_proxy":       config.Global.DefaultProxy,
+			"proxy_test_status":   getProxyTestStatus(),
+			"proxy_test_ip":       getProxyTestIP(),
 			"site_name":           config.Global.SiteName,
 			"mail_services_count": len(config.Global.MailServices),
 			"mail_services":       config.Global.MailServices,
@@ -260,6 +262,11 @@ func handleConfig(w http.ResponseWriter, r *http.Request) {
 		}
 		if req.DefaultProxy != nil {
 			config.Global.DefaultProxy = *req.DefaultProxy
+			// 代理地址变更时，重置测试状态
+			if database.Instance != nil {
+				database.Instance.SetConfig("proxy_test_status", "unknown")
+				database.Instance.SetConfig("proxy_test_ip", "")
+			}
 		}
 		if req.SiteName != nil {
 			config.Global.SiteName = *req.SiteName
@@ -1010,6 +1017,11 @@ func handleProxyTest(w http.ResponseWriter, r *http.Request) {
 
 	if resp.StatusCode != http.StatusOK {
 		logger.Error(fmt.Sprintf("代理测试失败: HTTP %d", resp.StatusCode), "", "proxy")
+		// 保存失败状态
+		if database.Instance != nil {
+			database.Instance.SetConfig("proxy_test_status", "error")
+			database.Instance.SetConfig("proxy_test_ip", "")
+		}
 		api.Error(w, http.StatusBadGateway, fmt.Sprintf("代理测试失败: HTTP %d", resp.StatusCode))
 		return
 	}
@@ -1024,6 +1036,12 @@ func handleProxyTest(w http.ResponseWriter, r *http.Request) {
 
 	logger.Success(fmt.Sprintf("代理连接成功, 出口IP: %s", ipResp.Origin), "", "proxy")
 
+	// 保存成功状态到数据库
+	if database.Instance != nil {
+		database.Instance.SetConfig("proxy_test_status", "success")
+		database.Instance.SetConfig("proxy_test_ip", ipResp.Origin)
+	}
+
 	api.Success(w, map[string]interface{}{
 		"connected": true,
 		"message":   "代理连接成功",
@@ -1031,6 +1049,26 @@ func handleProxyTest(w http.ResponseWriter, r *http.Request) {
 	})
 }
 
+// getProxyTestStatus 获取代理测试状态
+func getProxyTestStatus() string {
+	if database.Instance == nil {
+		return "unknown"
+	}
+	if val, _ := database.Instance.GetConfig("proxy_test_status"); val != "" {
+		return val
+	}
+	return "unknown"
+}
+
+// getProxyTestIP 获取代理测试出口IP
+func getProxyTestIP() string {
+	if database.Instance == nil {
+		return ""
+	}
+	val, _ := database.Instance.GetConfig("proxy_test_ip")
+	return val
+}
+
 // parseProxyURL 解析代理 URL
 func parseProxyURL(proxyURL string) (*url.URL, error) {
 	// 如果没有协议前缀，默认添加 http://