feat(rdp): 新增 RDP 远程桌面/SMB/账单同步能力 + 清理编译产物

主要变更：
- RDP 远程桌面：新增 backend/pkg/rdp（RDP 引擎 + credssp/display/rle/trace）、
  backend/controller/rdp*（连接/凭证/文件/会话/实时）、frontend RDP 组件与 API
- Windows SMB 文件传输：backend/pkg/winsmb
- 云账单同步：backend/pkg/billingsync + billing_sync/aliyun_billing，前端账单详情
- Agent CLI Kubernetes 工具：kubernetes_action/get、pod_execute/logs
- 服务器导入助手：server_import_helpers、ImportCredentialSettings
- 国际化与组件重构（cloud/deploy/monitor/server/system 等多模块）
- 清理编译产物二进制：移除 backend/server、backend/agent/bin/aiops-agent-*
- .gitignore：新增 backend/agent/ 与 .cache/（避免 334MB go-build 缓存误入库）

Co-Authored-By: Claude <noreply@anthropic.com>

backend/cloud/aliyun.go

@@ -66,15 +66,56 @@ func (a *AliyunProvider) sign(params map[string]string) string {
 	return base64.StdEncoding.EncodeToString(mac.Sum(nil))
 }
 
-// call 调用阿里云 RPC API
+// call 调用阿里云 ECS RPC API
 func (a *AliyunProvider) call(action string, extra map[string]string, endpoint string) ([]byte, error) {
 	if endpoint == "" {
 		endpoint = "https://ecs.aliyuncs.com/"
 	}
+	return a.callWithVersion(action, extra, endpoint, a.version)
+}
 
+// aliyunBSSEndpoints BSS 国内站与国际站接入点（站点不匹配时需自动切换） // Logan.Li
+var aliyunBSSEndpoints = []string{
+	"https://business.aliyuncs.com/",                // 国内站 aliyun.com
+	"https://business.ap-southeast-1.aliyuncs.com/", // 国际站 alibabacloud.com
+}
+
+// callBSS 调用阿里云费用中心 BSS OpenAPI，自动适配国内/国际站 // Logan.Li
+func (a *AliyunProvider) callBSS(action string, extra map[string]string) ([]byte, error) {
+	var lastErr error
+	for _, endpoint := range aliyunBSSEndpoints {
+		body, err := a.callWithVersion(action, extra, endpoint, "2017-12-14")
+		if err == nil {
+			return body, nil
+		}
+		if isAliyunBSSSiteMismatch(err) {
+			lastErr = err
+			continue
+		}
+		return nil, err
+	}
+	if lastErr != nil {
+		return nil, fmt.Errorf("阿里云账单 API 站点不匹配（请确认 AK 属于国内站 aliyun.com 或国际站 alibabacloud.com）: %w", lastErr)
+	}
+	return nil, fmt.Errorf("阿里云账单 API 调用失败")
+}
+
+// isAliyunBSSSiteMismatch 判断是否为国内/国际站 endpoint 不匹配 // Logan.Li
+func isAliyunBSSSiteMismatch(err error) bool {
+	if err == nil {
+		return false
+	}
+	msg := err.Error()
+	return strings.Contains(msg, "NotApplicable") ||
+		strings.Contains(msg, "caller site") ||
+		strings.Contains(msg, "regionId")
+}
+
+// callWithVersion 通用阿里云 RPC 签名请求
+func (a *AliyunProvider) callWithVersion(action string, extra map[string]string, endpoint, version string) ([]byte, error) {
 	params := map[string]string{
 		"Format":           "JSON",
-		"Version":          a.version,
+		"Version":          version,
 		"AccessKeyId":      a.accessKey,
 		"SignatureMethod":  "HMAC-SHA1",
 		"Timestamp":        time.Now().UTC().Format("2006-01-02T15:04:05Z"),