feat: 新增风险图谱算法与系统仪表盘及操作反馈体系

后端新增风险图谱算法模块、风险观察与反馈服务、规则 DSL
校验器和可解释性引擎，完善系统仪表盘和财务仪表盘统计，
优化 agent 运行和编排执行链路，清理旧开发文档，前端新增
系统趋势、负载热力图等多种仪表盘图表组件，完善操作反馈
对话框和工作台日期选择器，优化报销创建和审批详情交互，
补充单元测试覆盖。

web/src/assets/styles/components/top-bar.css

@@ -124,6 +124,49 @@
   position: relative;
 }
 
+.dashboard-switch-wrap {
+  width: 190px;
+  flex: 0 0 190px;
+  height: 44px;
+  display: flex;
+  align-items: center;
+}
+
+.dashboard-switch-select {
+  width: 100%;
+}
+
+.dashboard-switch-select :deep(.el-select__wrapper) {
+  height: 44px;
+  min-height: 44px;
+  border-radius: 4px;
+  background: #f8fbfd;
+  box-shadow:
+    0 0 0 2px rgba(var(--theme-primary-rgb, 58, 124, 165), .48) inset,
+    0 1px 2px rgba(15, 23, 42, .05);
+}
+
+.dashboard-switch-select :deep(.el-select__wrapper:hover) {
+  background: #f3f9fd;
+  box-shadow:
+    0 0 0 2px rgba(var(--theme-primary-rgb, 58, 124, 165), .72) inset,
+    0 0 0 3px rgba(var(--theme-primary-rgb, 58, 124, 165), .08);
+}
+
+.dashboard-switch-select :deep(.el-select__wrapper.is-focused) {
+  background: #ffffff;
+  box-shadow:
+    0 0 0 2px var(--theme-primary) inset,
+    0 0 0 3px rgba(var(--theme-primary-rgb, 58, 124, 165), .14);
+}
+
+.dashboard-switch-select :deep(.el-select__placeholder),
+.dashboard-switch-select :deep(.el-select__selected-item) {
+  color: #1e293b;
+  font-size: 13px;
+  font-weight: 800;
+}
+
 .custom-range-btn {
   height: 42px;
   display: inline-flex;
@@ -507,6 +550,11 @@
     justify-content: center;
   }
 
+  .dashboard-switch-wrap {
+    width: 100%;
+    flex: 1 1 100%;
+  }
+
   .calendar-popover {
     right: auto;
     left: 0;