feat: 搭建微信小程序展示端

- 初始化小程序工程配置与类型声明

- 增加首页、律所、律师列表、详情与历史页面

- 补充公共组件、运行时配置与示例素材

frontend_miniprogram/miniprogram/utils/miniapp.ts

@@ -0,0 +1,29 @@
+import type { MiniProgramEnvVersion } from '../config/runtime';
+
+const APPID_OVERRIDE_KEY = 'miniapp_appid_override';
+
+export function getMiniappAppId(): string {
+  const override = wx.getStorageSync(APPID_OVERRIDE_KEY);
+  if (typeof override === 'string' && override.trim()) {
+    return override.trim();
+  }
+
+  try {
+    const accountInfo = wx.getAccountInfoSync();
+    return accountInfo.miniProgram.appId || '';
+  } catch {
+    return '';
+  }
+}
+
+export function getMiniappEnvVersion(): MiniProgramEnvVersion {
+  try {
+    const envVersion = wx.getAccountInfoSync().miniProgram.envVersion;
+    if (envVersion === 'trial' || envVersion === 'release') {
+      return envVersion;
+    }
+    return 'develop';
+  } catch {
+    return 'develop';
+  }
+}