feat(player): 完善 H5 投注端与 API 演示数据

- 球赛/串关/优胜冠军、赛事详情、历史投注与个人资料编辑
- 固定顶栏、公告与底栏，仅内容区滚动
- 底部导航与站点 favicon 使用 logo，登录页精简
- API 种子、冠军盘与历史注单增强

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/player/src/components/LocaleFlag.vue

@@ -0,0 +1,32 @@
+<script setup lang="ts">
+import { computed } from 'vue';
+import { getLocaleDisplay } from '../utils/localeDisplay';
+
+const props = withDefaults(
+  defineProps<{ locale: string; size?: number }>(),
+  { size: 20 },
+);
+
+const countryCode = computed(() => getLocaleDisplay(props.locale).countryCode);
+const src = computed(() => `/flags/${countryCode.value}.svg`);
+</script>
+
+<template>
+  <img
+    :src="src"
+    :width="size"
+    :height="Math.round(size * 0.67)"
+    class="locale-flag"
+    :alt="countryCode"
+  />
+</template>
+
+<style scoped>
+.locale-flag {
+  display: block;
+  flex-shrink: 0;
+  border-radius: 2px;
+  object-fit: cover;
+  box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.12);
+}
+</style>