优化: 会话状态键控与提示补全

- 队列清空/发送失败补提示,错误接入分类文案
- 审批超时气泡按会话归属,流守卫按会话清理
- 会话操作失败就近反馈,拖拽非法流转提示原因

src/composables/task/useTaskKanban.ts

@@ -2,7 +2,7 @@ import { ref } from 'vue'
 import Sortable from 'sortablejs'
 import { useI18n } from 'vue-i18n'
 import { taskApi } from '@/api/task'
-import { TASK_STATUS_TRANSITIONS } from '@/constants/project'
+import { TASK_STATUS_TRANSITIONS, taskStatusLabel } from '@/constants/project'
 import { useToast } from '../useToast'
 
 export function useTaskKanban(opts: {
@@ -15,6 +15,8 @@ export function useTaskKanban(opts: {
   let s: Sortable[] = []
   let _dragId: string | null = null
   let _executing = false
+  // 最近一次被拒的流转方向:onMove 只记录不提示(避免拖拽悬停过程误报),onEnd 弹回时消费并清空
+  let _rejected: { from: string; to: string } | null = null
 
   function destroy() { s.forEach(x => x.destroy()); s = [] }
 
@@ -30,12 +32,16 @@ export function useTaskKanban(opts: {
         onMove: (e) => {
           const from = (e.from as HTMLElement).dataset.status ?? ''
           const to = ((e.to as HTMLElement).closest('[data-status]') as HTMLElement)?.dataset.status ?? ''
-          if (from === to) return true
-          return TASK_STATUS_TRANSITIONS[from]?.includes(to) ?? false
+          if (from === to) { _rejected = null; return true }
+          const legal = TASK_STATUS_TRANSITIONS[from]?.includes(to) ?? false
+          // UX走查 P2-5:非法流转只记录方向;合法流转清掉旧拒绝,避免陈旧标记污染后续 onEnd 判断
+          _rejected = legal ? null : { from, to }
+          return legal
         },
         onStart: (e) => {
           _dragId = (e.item as HTMLElement).dataset.taskId ?? null
           _executing = false
+          _rejected = null
         },
         onEnd: async (e) => {
           if (_executing) return
@@ -44,7 +50,22 @@ export function useTaskKanban(opts: {
           const to = ((e.to as HTMLElement).closest('[data-status]') as HTMLElement)?.dataset.status
           const id = _dragId
           _dragId = null
-          if (!to || !from || to === from) { _executing = false; return }
+          if (!to || !from || to === from) {
+            // UX走查 P2-5:非法流转被 onMove 拒绝时卡片弹回原列(落点 to===from),
+            // 此处补一条原因 toast,替代原先的静默弹回(原因与父卡 tooltip 同源:状态机流转表)
+            if (_rejected) {
+              showToast(
+                t('tasks.kanban.illegalMove', {
+                  from: t(taskStatusLabel(_rejected.from)),
+                  to: t(taskStatusLabel(_rejected.to)),
+                }),
+                'error',
+              )
+              _rejected = null
+            }
+            _executing = false
+            return
+          }
           if (!id) { _executing = false; return }
           kanbanBusy.value = true
           try {