refactor: swap custom CheckBox for Vant Checkbox

delete unused custom CheckBox component files including .vue, style and doc files
update login page template and imports to use van-checkbox
add VanCheckbox type definitions to global components declarations

src/pages/login/index.vue

@@ -4,14 +4,14 @@
     <img class="w-[200px] h-[200px]" :src="logo" />
 
     <!-- 协议勾选 -->
-    <div class="w-[304px] mt-[80px] flex items-center">
-      <CheckBox v-model="isAgree">
+    <div class="w-[304px] mt-[80px]">
+      <van-checkbox v-model="isAgree">
         <span class="text-[12px] text-ink-600">我已阅读并同意</span>
         <span class="text-[12px] text-[#2D91FF] mx-[4px]" @click.stop="handleAgreeClick('service')">《服务协议》</span>
         <span class="text-[12px] text-ink-600">和</span>
         <span class="text-[12px] text-[#2D91FF] mx-[4px]" @click.stop="handleAgreeClick('privacy')">《隐私协议》</span>
         <span class="text-[12px] text-ink-600 ml-[30px]">授权与账号关联操作</span>
-      </CheckBox>
+      </van-checkbox>
     </div>
 
     <!-- 按钮区域 -->
@@ -29,7 +29,6 @@
 import { ref, computed } from "vue";
 import { getServiceAgreement, getPrivacyAgreement } from "@/api/login";
 import { onLogin, goBack, onCheckPhoneLogin, onAppleLogin } from "@/hooks/useGoLogin";
-import CheckBox from "@/components/CheckBox/index.vue";
 import AgreePopup from "./components/AgreePopup/index.vue";
 
 // 是否需要微信手机号授权登录