feat: Add SendSms component for sending SMS verification code

src/components/send-sms.vue

@@ -0,0 +1,12 @@
+<template>
+  <van-button type="primary" @click="triggerCountdown" :disabled="isCounting">
+    发送验证码
+    {{ !isCounting ? '' : `(${countdownTime}s)` }}
+  </van-button>
+</template>
+
+<script setup lang="ts">
+import { useCountdown } from 'utils4u/vue-use';
+
+const { countdownTime, triggerCountdown, isCounting } = useCountdown(3);
+</script>