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_billing.go

@@ -0,0 +1,141 @@
+package cloud
+
+import (
+	"encoding/json"
+	"fmt"
+	"math"
+	"strconv"
+	"strings"
+)
+
+// FetchDailyBill 拉取指定日期的阿里云日账单（按产品+地域聚合） // Logan.Li
+func (a *AliyunProvider) FetchDailyBill(billingDate string) ([]CloudBillingRecord, error) {
+	if len(billingDate) != 10 {
+		return nil, fmt.Errorf("账单日期格式应为 YYYY-MM-DD")
+	}
+	billingCycle := billingDate[:7]
+
+	type aggKey struct {
+		service string
+		region  string
+	}
+	agg := map[aggKey]float64{}
+	currency := "CNY"
+
+	pageNum := 1
+	pageSize := 300
+	totalCount := -1
+
+	for {
+		body, err := a.callBSS("QueryInstanceBill", map[string]string{
+			"BillingCycle":     billingCycle,
+			"BillingDate":      billingDate,
+			"Granularity":      "DAILY",
+			"PageNum":          strconv.Itoa(pageNum),
+			"PageSize":         strconv.Itoa(pageSize),
+			"IsHideZeroCharge": "true",
+		})
+		if err != nil {
+			return nil, err
+		}
+
+		var resp aliyunInstanceBillResponse
+		if err := json.Unmarshal(body, &resp); err != nil {
+			return nil, fmt.Errorf("解析账单响应失败: %w", err)
+		}
+		if !resp.Success && resp.Code != "Success" {
+			msg := resp.Message
+			if msg == "" {
+				msg = string(body)
+			}
+			return nil, fmt.Errorf("阿里云账单 API 错误: %s", msg)
+		}
+
+		if totalCount < 0 {
+			totalCount = resp.Data.TotalCount
+		}
+
+		items := normalizeBillItems(resp.Data.Items.Item)
+		for _, it := range items {
+			amount := it.PretaxAmount
+			if amount <= 0 {
+				amount = it.PaymentAmount
+			}
+			if amount <= 0 {
+				continue
+			}
+			service := strings.TrimSpace(it.ProductName)
+			if service == "" {
+				service = strings.TrimSpace(it.ProductCode)
+			}
+			if service == "" {
+				service = "其他"
+			}
+			region := strings.TrimSpace(it.Region)
+			if region == "" {
+				region = "全局"
+			}
+			key := aggKey{service: service, region: region}
+			agg[key] += amount
+			if it.Currency != "" {
+				currency = it.Currency
+			}
+		}
+
+		if len(items) == 0 || pageNum*pageSize >= totalCount {
+			break
+		}
+		pageNum++
+	}
+
+	records := make([]CloudBillingRecord, 0, len(agg))
+	for key, cost := range agg {
+		records = append(records, CloudBillingRecord{
+			BillingDate: billingDate,
+			Provider:    "aliyun",
+			Cost:        math.Round(cost*100) / 100,
+			Currency:    currency,
+			Service:     key.service,
+			Region:      key.region,
+			Description: "云API自动同步（阿里云 QueryInstanceBill）",
+		})
+	}
+	return records, nil
+}
+
+type aliyunInstanceBillResponse struct {
+	Code    string `json:"Code"`
+	Message string `json:"Message"`
+	Success bool   `json:"Success"`
+	Data    struct {
+		TotalCount int `json:"TotalCount"`
+		Items      struct {
+			Item json.RawMessage `json:"Item"`
+		} `json:"Items"`
+	} `json:"Data"`
+}
+
+type aliyunBillItem struct {
+	ProductCode   string  `json:"ProductCode"`
+	ProductName   string  `json:"ProductName"`
+	Region        string  `json:"Region"`
+	PretaxAmount  float64 `json:"PretaxAmount"`
+	PaymentAmount float64 `json:"PaymentAmount"`
+	Currency      string  `json:"Currency"`
+}
+
+// normalizeBillItems 兼容 Item 为对象或数组两种返回格式 // Logan.Li
+func normalizeBillItems(raw json.RawMessage) []aliyunBillItem {
+	if len(raw) == 0 || string(raw) == "null" {
+		return nil
+	}
+	var items []aliyunBillItem
+	if err := json.Unmarshal(raw, &items); err == nil {
+		return items
+	}
+	var one aliyunBillItem
+	if err := json.Unmarshal(raw, &one); err == nil {
+		return []aliyunBillItem{one}
+	}
+	return nil
+}