feat: 添加聊天页面和钱包卡组件，优化用户界面和余额格式化逻辑

src/utils/helper.ts

@@ -0,0 +1,6 @@
+export function formatBalance(amount: MaybeRefOrGetter<number>, locale: Intl.LocalesArgument = "en-US"): ComputedRef<string> {
+  return computed(() => {
+    const balance = toValue(amount);
+    return `$${balance.toLocaleString(locale, { minimumFractionDigits: 2, maximumFractionDigits: 2 })}`;
+  });
+}