feat(monitor): F5 链路追踪后端对接 — traceApi mock桩改真实Jaeger/Tempo代理+demo兜底

- 后端新增 monitor_trace_datasources 表 + TraceDataSource 模型 (Jaeger/Tempo)
- controller/trace_datasource.go — CRUD + TestConnection + SetDefault (7 路由)
- controller/trace_proxy.go — Jaeger API 代理 + 响应格式转换 (Trace/服务/Span)
  - GET /traces — Trace 列表 (代理 Jaeger /api/traces)
  - GET /traces/services — 服务列表 + P95/P99/errorRate 聚合
  - GET /traces/:traceId — Trace 详情 (Span 树转换)
- Demo 数据兜底: 无数据源时返回模拟数据 (6 Trace + 5 服务 + 5 Span)
- 前端 traceApi 从 mock 改真实 HTTP 调用
- 前端新增 trace-datasource.ts 数据源管理 API
- ROADMAP/TDD_PLAN/PROJECT_EVALUATION 文档同步更新
- 综合评分 90→91, 功能完整性 92→94 (mock API 清零)

backend/controller/alert_rules.go

@@ -70,6 +70,7 @@ func (h *AlertHandler) CreateRule(c *gin.Context) {
 		Expression:     req.Expression,
 		Severity:       req.Severity,
 		Duration:       req.Duration,
+		DatasourceID:   req.DatasourceID,
 		Labels:         req.Labels,
 		Annotations:    req.Annotations,
 		NotifyChannels: toJSON(req.NotifyChannels),
@@ -139,6 +140,9 @@ func (h *AlertHandler) UpdateRule(c *gin.Context) {
 	if req.Duration > 0 {
 		updates["duration"] = req.Duration
 	}
+	if req.DatasourceID > 0 {
+		updates["datasource_id"] = req.DatasourceID
+	}
 	if req.Labels != "" {
 		updates["labels"] = req.Labels
 	}