feat: 报销预审会话状态管理与工作台交互增强

- 新增差旅报销会话状态管理与对话模型重构
- 增强风险观测服务与运行时聊天上下文作用域
- 优化工作台图标资源、助理意图识别与摘要工具
- 完善报销创建视图样式与差旅详情页标准调整交互
- 补充风险观测、运行时聊天与报销端点测试覆盖

web/src/assets/styles/views/travel-reimbursement-create-view-part4.css

@@ -62,6 +62,97 @@
   background: #fff;
 }
 
+.steward-plan-block {
+  margin-top: 12px;
+  display: grid;
+  gap: 10px;
+}
+
+.steward-task-card,
+.steward-attachment-card {
+  border: 1px solid #dbe7f2;
+  border-radius: 4px;
+  background: #f8fbfe;
+}
+
+.steward-task-list,
+.steward-attachment-list {
+  display: grid;
+  gap: 8px;
+}
+
+.steward-task-card,
+.steward-attachment-card {
+  padding: 10px 12px;
+}
+
+.steward-task-card header,
+.steward-attachment-card header {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  margin-bottom: 6px;
+}
+
+.steward-task-card header span,
+.steward-attachment-card header span {
+  color: #24618a;
+  font-size: 12px;
+  font-weight: 700;
+}
+
+.steward-task-card header small,
+.steward-attachment-card header small {
+  margin-left: auto;
+  color: #71879b;
+  font-size: 12px;
+}
+
+.steward-task-card > strong {
+  display: block;
+  color: #1f3448;
+  font-size: 14px;
+}
+
+.steward-task-card p,
+.steward-attachment-card p {
+  margin: 5px 0 0;
+  color: #5c7185;
+  font-size: 12px;
+  line-height: 1.55;
+}
+
+.steward-task-meta,
+.steward-attachment-chip-row {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 6px;
+  margin-top: 8px;
+}
+
+.steward-task-meta span,
+.steward-attachment-chip {
+  border: 1px solid #d5e2ee;
+  border-radius: 4px;
+  background: #fff;
+  color: #49677f;
+  font-size: 12px;
+  line-height: 1.4;
+  padding: 3px 7px;
+}
+
+.steward-attachment-chip.include {
+  border-color: #c7deef;
+  background: #eef7fc;
+  color: #24618a;
+}
+
+.steward-attachment-chip.exclude {
+  border-color: #ecd6c4;
+  background: #fff8f2;
+  color: #8a5a24;
+}
+
 .welcome-quick-actions {
   margin-top: 14px;
   padding-top: 12px;