feat(demo-vue): update contact information with i18n support

- Replaced hardcoded contact details in FooterComponent.vue with localized strings using the t() function.
- Updated English and Chinese locale files to include new contact information for phone, email, and WeChat/WhatsApp.

demo-vue/src/components/FooterComponent.vue

@@ -32,11 +32,11 @@
           <div class="contact-info">
             <div class="contact-item">
               <el-icon class="contact-icon"><Phone /></el-icon>
-              <span>+8613815368088</span>
+              <span>{{ t('common.contactPhoneLine') }}</span>
             </div>
             <div class="contact-item">
               <el-icon class="contact-icon"><Message /></el-icon>
-              <span>contact@lvbaoelectric.com</span>
+              <span>{{ t('common.contactEmailLine') }}</span>
             </div>
             <div class="contact-item">
               <el-icon class="contact-icon"><Location /></el-icon>
@@ -44,7 +44,7 @@
             </div>
             <div class="contact-item">
               <el-icon class="contact-icon"><ChatDotRound /></el-icon>
-              <span>WhatsApp: +13026946050</span>
+              <span>{{ t('common.contactWechatLine') }}</span>
             </div>
           </div>
         </div>

demo-vue/src/locales/en-US/messages.ts

@@ -45,7 +45,11 @@ export const messages = {
     allRights: 'All rights reserved',
     copyrightFull: 'Copyright © 2026 Shandong Showdart Technology Engineering Co., Ltd. All rights reserved.',
     companyInfo: 'Company',
-    addressLabel: 'Cunqian Village, Huangli Town, Wujin District, Changzhou, Jiangsu, China'
+    addressLabel:
+      'A4, Smart Valley, Economic and Technological Development Zone, Jining City, Shandong Province, China.',
+    contactPhoneLine: 'Tel: +86 177 144 33303',
+    contactEmailLine: 'amaransalesgroup@163.com',
+    contactWechatLine: 'Wechat & WhatsApp: +86 177 144 33303'
   },
   language: { zh: '中文', en: 'English', switch: 'Language' },
   nav: {

demo-vue/src/locales/zh-CN/messages.ts

@@ -45,7 +45,10 @@ export const messages = {
     allRights: '保留所有权利',
     copyrightFull: '版权所有 © 2026 山东首达特科技工程有限公司 保留所有权利。',
     companyInfo: '公司信息',
-    addressLabel: '中国江苏省常州市武进区湟里镇村前村'
+    addressLabel: '中国山东省济宁市经济技术开发区智慧谷A4',
+    contactPhoneLine: '手机：+86 177 144 33303',
+    contactEmailLine: 'amaransalesgroup@163.com',
+    contactWechatLine: '微信 & WhatsApp：+86 177 144 33303'
   },
   language: { zh: '中文', en: 'English', switch: '语言' },
   nav: {