feat: 收支记录批量操作按钮移至表格右上角并优化一键设置作用范围

将批量相关按钮从页头工具栏集中到列表右上角，并让一键设置优先作用于勾选记录、未勾选时作用于当前页全部记录，同时补充区分来源的作用范围提示文案。

变更内容：
- 将「批量操作／退出批量、一键设置、批量删除、建立关系」移至列表右上角（分页统计信息上方）
- 一键设置以打开弹窗时的目标快照为准：有勾选时作用于勾选记录，未勾选时作用于当前页全部记录
- 作用范围提示区分「已勾选」与「未勾选（当前表格展示）」两种文案
- 新增中英日三语文案 batchScopeHintSelected / batchScopeHintPage，移除旧 batchScopeHint

说明：
- 顺带移除 LoginRequest 未使用的 Size 导入与 AiSuggestionServiceImpl 未使用的 BigDecimal 导入

frontend/src/views/TransactionList.vue

@@ -218,9 +218,15 @@ const batchIncludeInStats = ref<'null' | 'true' | 'false'>('null') // 批量设
 const batchAddTagIds = ref<number[]>([]) // 批量添加的标签
 const batchRemoveTagIds = ref<number[]>([]) // 批量移除的标签
 const batching = ref(false) // 批量设置提交状态
-// 当前表格是否包含收入/支出记录，用于按需展示批量分类项
-const hasIncomeRecords = computed(() => transactions.value.some((tx) => tx.type === 'INCOME'))
-const hasExpenseRecords = computed(() => transactions.value.some((tx) => tx.type === 'EXPENSE'))
+// 一键设置目标记录快照：有勾选时取勾选记录，否则取当前表格展示的记录
+const batchTargets = ref<TransactionItem[]>([])
+// 目标记录是否来自勾选，用于作用范围提示文案
+const batchFromSelection = ref(false)
+// 目标记录ID列表
+const batchTargetIds = computed(() => batchTargets.value.map((tx) => tx.id))
+// 一键设置目标中是否包含收入/支出记录，用于按需展示批量分类项
+const hasIncomeRecords = computed(() => batchTargets.value.some((tx) => tx.type === 'INCOME'))
+const hasExpenseRecords = computed(() => batchTargets.value.some((tx) => tx.type === 'EXPENSE'))
 
 // 批量设置计入统计选项
 const batchStatsOptions = computed(() => [
@@ -943,13 +949,13 @@ async function loadAiConfig() {
 
 /** 请求 AI 建议：对当前表格展示的记录生成分类与标签建议 */
 async function handleAiSuggest() {
-  if (transactions.value.length === 0) {
+  if (batchTargetIds.value.length === 0) {
     message.warning(t('transaction.noRecordsToSet'))
     return
   }
   aiLoading.value = true
   try {
-    const ids = transactions.value.map((tx) => tx.id)
+    const ids = batchTargetIds.value
     const res: any = await suggestByAi(ids, aiScope.value)
     aiSuggestions.value = res.data || []
     if (aiSuggestions.value.length === 0) {
@@ -1896,12 +1902,19 @@ function renderTagsCell(row: AiSuggestion) {
   return items.length > 0 ? h(NSpace, { size: 4, wrap: true }, { default: () => items }) : '-'
 }
 
-/** 打开批量设置分类弹窗 */
+/** 打开批量设置分类弹窗：有勾选时作用于勾选记录，否则作用于当前表格展示的记录 */
 function handleBatchOpen() {
-  if (transactions.value.length === 0) {
+  // 勾选记录均属于当前页，按ID过滤当前页即可得到目标记录
+  const hasSelection = checkedTransactionIds.value.length > 0
+  const targets = hasSelection
+    ? transactions.value.filter((tx) => checkedTransactionIds.value.includes(tx.id))
+    : [...transactions.value]
+  if (targets.length === 0) {
     message.warning(t('transaction.noRecordsToSet'))
     return
   }
+  batchTargets.value = targets
+  batchFromSelection.value = hasSelection
   batchExpenseCategoryId.value = null
   batchIncomeCategoryId.value = null
   batchIncludeInStats.value = 'null'
@@ -1920,7 +1933,7 @@ async function handleBatchSubmit() {
   }
   batching.value = true
   try {
-    const ids = transactions.value.map((tx) => tx.id)
+    const ids = batchTargetIds.value
     if (hasCategoryOrStats) {
       await batchUpdateCategory({
         ids,
@@ -2024,15 +2037,6 @@ onBeforeUnmount(() => {
         <span style="color: #999; font-size: 13px;">{{ t('transaction.sortLabel') }}</span>
         <NSelect v-model:value="sortValue" :options="sortOptions" style="width: 170px;" />
         <NDivider vertical style="margin: 0 4px;" />
-        <NButton v-if="!selectionMode" @click="enterSelectionMode">{{ t('transaction.batchMode') }}</NButton>
-        <NButton v-else @click="exitSelectionMode">{{ t('transaction.exitBatchMode') }}</NButton>
-        <NButton @click="handleBatchOpen">{{ t('transaction.batchSet') }}</NButton>
-        <NButton v-if="checkedTransactionIds.length > 0" type="error" @click="handleBatchDelete">
-          {{ t('transaction.batchDelete') }}
-        </NButton>
-        <NButton v-if="checkedTransactionIds.length >= 2" type="primary" ghost @click="handleCreateRelation">
-          {{ t('transaction.relation.createFromSelection') }}
-        </NButton>
         <NButton @click="showImportModal = true">{{ t('transaction.importBill') }}</NButton>
         <NButton @click="goChannelManage">{{ t('channel.manageEntry') }}</NButton>
         <NButton :loading="exporting" @click="handleExport">{{ t('transaction.exportExcel') }}</NButton>
@@ -2199,6 +2203,19 @@ onBeforeUnmount(() => {
       </div>
     </NCard>
 
+    <!-- 表格右上角：批量操作按钮 -->
+    <NSpace justify="end" align="center" :size="12" style="margin-bottom: 8px;" :wrap="true">
+      <NButton v-if="!selectionMode" @click="enterSelectionMode">{{ t('transaction.batchMode') }}</NButton>
+      <NButton v-else @click="exitSelectionMode">{{ t('transaction.exitBatchMode') }}</NButton>
+      <NButton @click="handleBatchOpen">{{ t('transaction.batchSet') }}</NButton>
+      <NButton v-if="checkedTransactionIds.length > 0" type="error" @click="handleBatchDelete">
+        {{ t('transaction.batchDelete') }}
+      </NButton>
+      <NButton v-if="checkedTransactionIds.length >= 2" type="primary" ghost @click="handleCreateRelation">
+        {{ t('transaction.relation.createFromSelection') }}
+      </NButton>
+    </NSpace>
+
     <!-- 表格信息栏（右上角） -->
     <NSpace justify="end" align="center" :size="12" style="margin-bottom: 8px;">
       <span style="color: #999; font-size: 12px;">
@@ -2349,7 +2366,9 @@ onBeforeUnmount(() => {
       <NForm>
         <NFormItem :label="t('transaction.batchScope')">
           <span style="color: #999; font-size: 12px;">
-            {{ t('transaction.batchScopeHint', { count: transactions.length }) }}
+            {{ batchFromSelection
+              ? t('transaction.batchScopeHintSelected', { count: batchTargets.length })
+              : t('transaction.batchScopeHintPage', { count: batchTargets.length }) }}
           </span>
         </NFormItem>
         <NFormItem v-if="aiEnabled" :label="t('ai.suggestButton')">