fix(ui): Toast 撤销可暂停，存储告警提升为全局

- Toast 自动关闭支持悬停/聚焦暂停，移开后按剩余时间继续
- 存储异常提示移到 App 级，看板与今日视图都能看到
- 归档隐藏与筛选隐藏分开说明，并提示列内排序暂停原因

src/views/BoardView.vue

@@ -19,8 +19,7 @@ const store = useTaskStore()
 const filters = useFilterStore()
 const toast = useToastStore()
 const ui = useUiStore()
-const { notice } = storeToRefs(store)
-const { filter } = storeToRefs(filters)
+const { filter, includeArchived } = storeToRefs(filters)
 
 /** 详情抽屉当前编辑的任务 id；任务被删除后自动变为 null，抽屉随之关闭 */
 const editingId = ref<string | null>(null)
@@ -54,6 +53,38 @@ const hiddenTotal = computed(() =>
   COLUMNS.reduce((total, column) => total + hiddenCounts.value[column.id], 0),
 )
 
+/**
+ * 被「隐藏归档」挡掉、且本来能通过当前筛选的任务数。
+ *
+ * 单独算一遍是为了给提示分层：用户看到「已隐藏 3 个」时，
+ * 应该知道其中多少是搜索/筛选造成的、多少只是归档没显示。
+ */
+const archivedHiddenTotal = computed(() => {
+  if (includeArchived.value) return 0
+  const archived = store.tasks.filter((task) => task.archivedAt !== null)
+  // filter.includeArchived 为 false 时会把归档任务直接排除，这里显式放开
+  return filterTasks(archived, { ...filter.value, includeArchived: true }).length
+})
+
+const filteredHiddenTotal = computed(() =>
+  Math.max(0, hiddenTotal.value - archivedHiddenTotal.value),
+)
+
+/**
+ * 列内排序在「渲染的是子集」时会被禁用（见 drag.ts），
+ * 这里把原因写出来，避免用户拖不动却不知道为什么。
+ */
+const hiddenNote = computed(() => {
+  if (hiddenTotal.value === 0) return undefined
+
+  const reasons: string[] = []
+  if (filteredHiddenTotal.value > 0) reasons.push(`筛选 ${filteredHiddenTotal.value}`)
+  if (archivedHiddenTotal.value > 0) reasons.push(`归档 ${archivedHiddenTotal.value}`)
+  const detail = reasons.length > 0 ? `（${reasons.join(' + ')}，列内排序已暂停）` : ''
+
+  return `已隐藏 ${hiddenTotal.value} 个${detail}`
+})
+
 const archivableTasks = computed(() => findArchivableTasks(store.tasks))
 
 function archiveCompleted(): void {
@@ -137,16 +168,10 @@ function handleKeyMove(payload: { id: string; direction: MoveDirection }): void
   <div class="flex min-h-0 flex-1 flex-col gap-3 p-4 md:p-6">
     <BoardToolbar
       ref="toolbarRef"
-      :hidden-note="hiddenTotal > 0 ? `· 已隐藏 ${hiddenTotal} 个` : undefined"
+      :hidden-note="hiddenNote"
       @archive="archiveCompleted"
     />
 
-    <p
-      v-if="notice"
-      class="rounded-lg border border-amber-300 bg-amber-50 px-3 py-2 text-sm text-amber-800"
-    >
-      {{ notice }}
-    </p>
 
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