feat(i18n): 管理端与玩家端三语支持（中/英/马来语）

- 管理后台 adminT 文案库、结算与代理端页面、表单校验
- 玩家端 vue-i18n 补全首页/公告/串关与 ms 文案
- Element Plus ms 语言包与共享 locale 工具

apps/admin/src/views/Cashback.vue

@@ -1,7 +1,10 @@
 <script setup lang="ts">
 import { ref } from 'vue';
-import api from '../api';
 import { ElMessage } from 'element-plus';
+import { useAdminLocale } from '../composables/useAdminLocale';
+import api from '../api';
+
+const { t } = useAdminLocale();
 
 const preview = ref<Record<string, unknown> | null>(null);
 const period = ref({
@@ -20,7 +23,7 @@ async function generatePreview() {
 async function confirm() {
   if (!preview.value?.batch) return;
   await api.post(`/admin/cashbacks/${(preview.value.batch as { id: string }).id}/confirm`);
-  ElMessage.success('返水已发放');
+  ElMessage.success(t('msg.cashback_issued'));
   preview.value = null;
 }
 </script>
@@ -28,43 +31,43 @@ async function confirm() {
 <template>
   <div class="page-scroll">
   <div class="page-header">
-    <h2 class="page-title">返水管理</h2>
-    <span class="page-desc">按周期生成返水并发放</span>
+    <h2 class="page-title">{{ t('page.cashback.title') }}</h2>
+    <span class="page-desc">{{ t('page.cashback.desc') }}</span>
   </div>
 
   <el-card class="tool-card" shadow="never">
     <div class="filter-row">
       <el-form inline>
-        <el-form-item label="开始日期">
+        <el-form-item :label="t('cashback.start_date')">
           <el-date-picker v-model="period.start" type="date" value-format="YYYY-MM-DD" style="width: 150px" />
         </el-form-item>
-        <el-form-item label="结束日期">
+        <el-form-item :label="t('cashback.end_date')">
           <el-date-picker v-model="period.end" type="date" value-format="YYYY-MM-DD" style="width: 150px" />
         </el-form-item>
         <el-form-item>
-          <el-button type="primary" @click="generatePreview">生成预览</el-button>
+          <el-button type="primary" @click="generatePreview">{{ t('cashback.preview_btn') }}</el-button>
         </el-form-item>
       </el-form>
     </div>
   </el-card>
 
   <el-card v-if="preview" class="preview-card" shadow="never">
-    <div class="preview-title">返水预览</div>
+    <div class="preview-title">{{ t('cashback.preview_title') }}</div>
     <el-row :gutter="20" class="preview-stats">
       <el-col :span="8">
         <div class="pstat">
           <div class="pstat-value">{{ (preview.batch as { playerCount: number })?.playerCount ?? 0 }}</div>
-          <div class="pstat-label">涉及玩家数</div>
+          <div class="pstat-label">{{ t('cashback.stat.players') }}</div>
         </div>
       </el-col>
       <el-col :span="8">
         <div class="pstat">
           <div class="pstat-value">{{ preview.totalAmount }}</div>
-          <div class="pstat-label">返水总金额</div>
+          <div class="pstat-label">{{ t('cashback.stat.total') }}</div>
         </div>
       </el-col>
     </el-row>
-    <el-button type="success" @click="confirm" style="margin-top: 20px">确认发放</el-button>
+    <el-button type="success" @click="confirm" style="margin-top: 20px">{{ t('cashback.confirm_issue') }}</el-button>
   </el-card>
   </div>
 </template>