perf: 子标签页按需加载（代码与元素懒加载）

原 v-show + 静态 import 导致三个子标签页的组件代码全部打进 MobileGame
chunk，且首屏即渲染全部（排行榜 onMounted 立即发 AJAX、视频元数据加载）。

改为：
- 三个标签页内容拆为独立组件 TeamLeaderboardTab/IterationsTab/ExperimentTab
- MobileGame 用 defineAsyncComponent + 动态 import，Vite 拆成独立 chunk
- v-if + Suspense：未激活的标签页组件根本不挂载（不发 AJAX、不渲染）
构建产物可见三个独立 chunk；headless 验证：默认团队页仅加载 team chunk，
点迭代记录才加载 IterationsTab chunk，点实验才加载 ExperimentTab chunk。

src/modules/mobile-game/components/ExperimentTab.vue

@@ -0,0 +1,48 @@
+<script setup>
+import { useI18n } from 'vue-i18n'
+
+const { locale } = useI18n({ useScope: 'global' })
+const L = (zh, en) => (locale.value === 'zh-CN' ? zh : en)
+// 站点根绝对路径，用绑定避免被 Vite 当作构建期静态资源解析
+const videoPoster = '/448/2.jpg'
+const videoSrc = '/448/ml/449ml.mp4'
+</script>
+
+<template>
+  <div class="tab-experiment">
+    <h2 class="section-title">
+      <small>{{ L('实验', 'Experiment') }}</small>
+      {{ L('ML-Agents 强化学习演示', 'ML-Agents Reinforcement Learning Demo') }}
+    </h2>
+    <div class="video-wrap">
+      <video controls preload="none" :poster="videoPoster">
+        <source :src="videoSrc" type="video/mp4" />
+      </video>
+      <p class="video-caption">
+        {{ L('胶囊体经 ML-Agents 训练，学习保球不掉与越障。', 'Capsules trained via ML-Agents to keep the ball from falling and to navigate obstacles.') }}
+      </p>
+    </div>
+  </div>
+</template>
+
+<style scoped>
+.video-wrap {
+  border: 1px solid var(--border);
+  border-radius: var(--radius);
+  overflow: hidden;
+  background: var(--surface);
+  box-shadow: var(--shadow-sm);
+}
+.video-wrap video {
+  width: 100%;
+  display: block;
+  aspect-ratio: 16 / 9;
+  background: #000;
+}
+.video-caption {
+  padding: var(--space-md) var(--space-lg);
+  font-size: 0.88rem;
+  color: var(--text-secondary);
+  margin: 0;
+}
+</style>

src/modules/mobile-game/components/IterationsTab.vue

@@ -0,0 +1,17 @@
+<script setup>
+import { useI18n } from 'vue-i18n'
+import VersionTimeline from './VersionTimeline.vue'
+
+const { locale } = useI18n({ useScope: 'global' })
+const L = (zh, en) => (locale.value === 'zh-CN' ? zh : en)
+</script>
+
+<template>
+  <div class="tab-iterations">
+    <h2 class="section-title">
+      <small>{{ L('版本演进', 'Version History') }}</small>
+      {{ L('迭代记录', 'Iteration Record') }}
+    </h2>
+    <VersionTimeline />
+  </div>
+</template>

src/modules/mobile-game/components/TeamLeaderboardTab.vue

@@ -0,0 +1,41 @@
+<script setup>
+import { useI18n } from 'vue-i18n'
+import TeamCard from './TeamCard.vue'
+import Leaderboard from './Leaderboard.vue'
+
+const { locale } = useI18n({ useScope: 'global' })
+const L = (zh, en) => (locale.value === 'zh-CN' ? zh : en)
+</script>
+
+<template>
+  <div class="tab-team block--two">
+    <div>
+      <h2 class="section-title">
+        <small>{{ L('团队', 'Team') }}</small>
+        {{ L('成员', 'Members') }}
+      </h2>
+      <TeamCard />
+    </div>
+    <div>
+      <h2 class="section-title">
+        <small>{{ L('排行榜', 'Leaderboard') }}</small>
+        {{ L('玩家分数 Top 30', 'Top 30 Scores') }}
+      </h2>
+      <Leaderboard />
+    </div>
+  </div>
+</template>
+
+<style scoped>
+.block--two {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: var(--space-xl);
+  align-items: start;
+}
+@media (max-width: 768px) {
+  .block--two {
+    grid-template-columns: 1fr;
+  }
+}
+</style>