重构 Play.vue 组件，拆分为多个子组件，提升代码可维护性和可读性。

主要变更：
- 将 Play.vue 拆分为 LoadingOverlay、SelectRegion、ScanPage、GamePage、RefreshWaitPage、ErrorPage 等组件
- 新增 composables 目录，分离业务逻辑（usePlayState、useTimers、useQrCode）
- 优化代码结构，提升开发效率和维护性

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/components/play/ErrorPage.vue

@@ -0,0 +1,83 @@
+<template>
+  <div class="error-page">
+    <div class="error-container">
+      <div class="error-icon">❌</div>
+      <h2 class="error-title">{{ errorTitle }}</h2>
+      <p class="error-message">{{ errorMessage }}</p>
+      <button @click="$emit('retry')" class="retry-btn">重新尝试</button>
+    </div>
+  </div>
+</template>
+
+<script>
+export default {
+  name: 'ErrorPage',
+  props: {
+    errorTitle: {
+      type: String,
+      required: true
+    },
+    errorMessage: {
+      type: String,
+      required: true
+    }
+  },
+  emits: ['retry']
+}
+</script>
+
+<style scoped>
+.error-page {
+  flex: 1;
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  padding: 40px 20px;
+}
+
+.error-container {
+  background: white;
+  padding: 40px;
+  border-radius: 20px;
+  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
+  text-align: center;
+  max-width: 400px;
+  width: 100%;
+}
+
+.error-icon {
+  font-size: 48px;
+  margin-bottom: 16px;
+}
+
+.error-title {
+  font-size: 20px;
+  font-weight: 600;
+  margin: 0 0 12px 0;
+  color: #333;
+}
+
+.error-message {
+  font-size: 16px;
+  color: #666;
+  margin: 0 0 24px 0;
+  line-height: 1.5;
+}
+
+.retry-btn {
+  background: #667eea;
+  color: white;
+  border: none;
+  padding: 12px 32px;
+  border-radius: 25px;
+  font-size: 16px;
+  font-weight: 600;
+  cursor: pointer;
+  transition: all 0.3s ease;
+}
+
+.retry-btn:hover {
+  background: #5a6fd8;
+  transform: translateY(-2px);
+}
+</style>