fix(web): steward plan 确认按钮直接拉起申请预览,不丢失 remaining tasks

根因:steward plan 的'确认创建申请单'按钮 action_type 是
ASSISTANT_SCOPE_ACTION_SWITCH,handleInlineSuggestedAction 没有匹配分支,
落到 startInlineConversation 重新发起对话,steward_remaining_tasks 完全丢失。

修复:当 payload 有 steward_current_task + session_type=application +
task_type=expense_application 时,直接调 startAiApplicationPreviewFromAction
(会透传 steward_remaining_tasks 到申请预览 message),不走 startInlineConversation。

这样保存草稿成功后,targetMessage 上有 stewardRemainingTasks,
buildApplicationPreviewNextTaskAction 能生成'继续处理费用报销'按钮。

web/src/composables/workbenchAiMode/useWorkbenchAiActionRouter.js

@@ -114,6 +114,17 @@ export function useWorkbenchAiActionRouter({
       void expenseFlow.startAiApplicationPreviewFromAction(actionPayload)
       return
     }
+    // steward plan 的"确认创建申请单"按钮:payload 有 steward_current_task + session_type=application,
+    // 直接拉起申请预览(带 remaining tasks),不走 startInlineConversation(会丢失 steward 上下文)
+    if (
+      actionPayload.steward_current_task
+      && String(actionPayload.session_type || '').trim() === 'application'
+      && String(actionPayload.steward_current_task.task_type || '').trim() === 'expense_application'
+    ) {
+      aiExpenseDraft.value = null
+      void expenseFlow.startAiApplicationPreviewFromAction(actionPayload)
+      return
+    }
     if (actionType === 'select_expense_type') {
       const expenseType = String(action?.payload?.expense_type || '').trim()
       const expenseTypeLabel = String(action?.payload?.expense_type_label || action?.label || '').trim()