fix(frontend): 批量编辑添加跨平台模型映射警告与过滤

- 新增 selectedPlatforms prop，从父组件传入选中账号的平台集合
- 根据选中平台过滤模型列表与预设映射按钮，避免误操作
- 混选多平台时显示 amber 警告横幅，提醒用户注意映射适用性
- 仅警告不阻断，保持加法兼容

frontend/src/views/admin/AccountsView.vue

@@ -259,7 +259,7 @@
     <AccountActionMenu :show="menu.show" :account="menu.acc" :position="menu.pos" @close="menu.show = false" @test="handleTest" @stats="handleViewStats" @reauth="handleReAuth" @refresh-token="handleRefresh" @reset-status="handleResetStatus" @clear-rate-limit="handleClearRateLimit" />
     <SyncFromCrsModal :show="showSync" @close="showSync = false" @synced="reload" />
     <ImportDataModal :show="showImportData" @close="showImportData = false" @imported="handleDataImported" />
-    <BulkEditAccountModal :show="showBulkEdit" :account-ids="selIds" :proxies="proxies" :groups="groups" @close="showBulkEdit = false" @updated="handleBulkUpdated" />
+    <BulkEditAccountModal :show="showBulkEdit" :account-ids="selIds" :selected-platforms="selPlatforms" :proxies="proxies" :groups="groups" @close="showBulkEdit = false" @updated="handleBulkUpdated" />
     <TempUnschedStatusModal :show="showTempUnsched" :account="tempUnschedAcc" @close="showTempUnsched = false" @reset="handleTempUnschedReset" />
     <ConfirmDialog :show="showDeleteDialog" :title="t('admin.accounts.deleteAccount')" :message="t('admin.accounts.deleteConfirm', { name: deletingAcc?.name })" :confirm-text="t('common.delete')" :cancel-text="t('common.cancel')" :danger="true" @confirm="confirmDelete" @cancel="showDeleteDialog = false" />
     <ConfirmDialog :show="showExportDataDialog" :title="t('admin.accounts.dataExport')" :message="t('admin.accounts.dataExportConfirmMessage')" :confirm-text="t('admin.accounts.dataExportConfirm')" :cancel-text="t('common.cancel')" @confirm="handleExportData" @cancel="showExportDataDialog = false">
@@ -303,7 +303,7 @@ import PlatformTypeBadge from '@/components/common/PlatformTypeBadge.vue'
 import Icon from '@/components/icons/Icon.vue'
 import ErrorPassthroughRulesModal from '@/components/admin/ErrorPassthroughRulesModal.vue'
 import { formatDateTime, formatRelativeTime } from '@/utils/format'
-import type { Account, Proxy, AdminGroup } from '@/types'
+import type { Account, AccountPlatform, Proxy, AdminGroup } from '@/types'
 
 const { t } = useI18n()
 const appStore = useAppStore()
@@ -312,6 +312,14 @@ const authStore = useAuthStore()
 const proxies = ref<Proxy[]>([])
 const groups = ref<AdminGroup[]>([])
 const selIds = ref<number[]>([])
+const selPlatforms = computed<AccountPlatform[]>(() => {
+  const platforms = new Set(
+    accounts.value
+      .filter(a => selIds.value.includes(a.id))
+      .map(a => a.platform)
+  )
+  return [...platforms]
+})
 const showCreate = ref(false)
 const showEdit = ref(false)
 const showSync = ref(false)