feat: add recipient address field to order form

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

web/product-intro/gut-testing.html

@@ -323,6 +323,10 @@
       <label style="display:block;font-size:0.85rem;color:var(--text-secondary);margin-bottom:0.3rem">手机号</label>
       <input id="orderPhone" type="tel" placeholder="请输入手机号" style="width:100%;padding:0.6rem 0.8rem;border:1px solid #e2e8f0;border-radius:8px;font-size:0.95rem;box-sizing:border-box">
     </div>
+    <div style="margin-bottom:1rem">
+      <label style="display:block;font-size:0.85rem;color:var(--text-secondary);margin-bottom:0.3rem">收件地址</label>
+      <input id="orderAddress" type="text" placeholder="省/市/区 + 详细地址" style="width:100%;padding:0.6rem 0.8rem;border:1px solid #e2e8f0;border-radius:8px;font-size:0.95rem;box-sizing:border-box">
+    </div>
     <div style="margin-bottom:1.2rem;padding:0.8rem;background:#f0fdfa;border-radius:8px;display:flex;justify-content:space-between;align-items:center">
       <span style="font-size:0.9rem;color:var(--text-secondary)">合计</span>
       <span style="font-size:1.5rem;font-weight:800;color:#0d9488">¥1,314</span>
@@ -336,8 +340,10 @@
 function submitOrder() {
   var name = document.getElementById('orderName').value.trim();
   var phone = document.getElementById('orderPhone').value.trim();
+  var address = document.getElementById('orderAddress').value.trim();
   if (!name) { alert('请输入联系人姓名'); return; }
   if (!phone || !/^1\d{10}$/.test(phone)) { alert('请输入正确的手机号'); return; }
+  if (!address) { alert('请输入收件地址'); return; }
   
   var btn = document.getElementById('payBtn');
   btn.disabled = true;