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/player/src/views/LoginView.vue

@@ -3,10 +3,13 @@ import { ref } from 'vue';
 import { useRouter } from 'vue-router';
 import { useI18n } from 'vue-i18n';
 import { useAuthStore } from '../stores/auth';
+import { useAppLocale } from '../composables/useAppLocale';
+import LocaleSwitcher from '../components/LocaleSwitcher.vue';
 import RobotVerify from '../components/RobotVerify.vue';
 import loginBg from '../assets/images/h5bg.png';
 
 const { t } = useI18n();
+const { initFromUser } = useAppLocale();
 const auth = useAuthStore();
 const router = useRouter();
 const captchaRef = ref<InstanceType<typeof RobotVerify> | null>(null);
@@ -25,6 +28,7 @@ async function submit() {
   error.value = '';
   try {
     await auth.login(username.value, password.value);
+    initFromUser(auth.user?.locale);
     router.push('/');
   } catch (e: unknown) {
     error.value = (e as { response?: { data?: { error?: string } } })?.response?.data?.error || 'Login failed';
@@ -36,6 +40,9 @@ async function submit() {
 
 <template>
   <div class="login-page" :style="{ backgroundImage: `url(${loginBg})` }">
+    <div class="login-lang">
+      <LocaleSwitcher compact />
+    </div>
     <form @submit.prevent="submit" class="login-form ps-gold-frame">
       <label>{{ t('auth.username') }}</label>
       <input v-model="username" class="ps-gold-input" required />
@@ -51,7 +58,15 @@ async function submit() {
 </template>
 
 <style scoped>
+.login-lang {
+  position: absolute;
+  top: max(12px, env(safe-area-inset-top));
+  right: 16px;
+  z-index: 2;
+}
+
 .login-page {
+  position: relative;
   height: 100%;
   min-height: 100dvh;
   overflow-y: auto;