fix: simplify payment QR instruction text

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

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

web/articles/enagic-turmeric.html

@@ -362,7 +362,7 @@ function showQrCode(codeUrl, orderNo, productName, amount) {
   div.style.cssText = 'position:fixed;top:0;left:0;right:0;bottom:0;background:rgba(0,0,0,0.5);z-index:1000;display:flex;align-items:center;justify-content:center';
   div.onclick = function(e) { if (e.target === this) this.remove(); };
   div.innerHTML = '<div style="background:#fff;border-radius:16px;padding:2rem;text-align:center;max-width:340px">' +
-    '<h3 style="margin-bottom:0.8rem;font-size:1.1rem;">请使用微信扫码支付</h3>' +
+    '<h3 style="margin-bottom:0.8rem;font-size:1.1rem;">用其他手机扫码支付</h3>' +
     '<div style="background:#f0fdfa;border-radius:8px;padding:0.8rem;margin-bottom:0.8rem;text-align:left">' +
       '<div style="font-size:0.85rem;color:var(--text-secondary);margin-bottom:0.3rem">' + productName + '</div>' +
       '<div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:0.3rem">' +
@@ -378,7 +378,7 @@ function showQrCode(codeUrl, orderNo, productName, amount) {
     '<div style="width:200px;height:200px;margin:0 auto 0.8rem;display:flex;align-items:center;justify-content:center;border-radius:8px;overflow:hidden">' +
       '<img src="/api/payment/qrcode?text=' + encodeURIComponent(codeUrl) + '" alt="支付二维码" style="width:200px;height:200px">' +
     '</div>' +
-    '<p style="font-size:0.8rem;color:#999">' + (typeof isWechatBrowser === 'function' && isWechatBrowser() ? '请截图保存二维码 → 打开微信扫一扫 → 从相册选择' : '打开微信「扫一扫」完成支付') + '</p>' +
+    '<p style="font-size:0.8rem;color:#999">请用其他手机微信扫码完成支付</p>' +
     '<button onclick="this.closest(\'div[style]\').remove()" style="margin-top:0.8rem;padding:0.5rem 2rem;border:1px solid #e2e8f0;border-radius:8px;background:#fff;cursor:pointer">取消支付</button>' +
     '</div>';
   document.body.appendChild(div);

web/product-intro/gut-testing.html

@@ -520,7 +520,7 @@ function showQrCode(codeUrl, orderNo) {
   div.style.cssText = 'position:fixed;top:0;left:0;right:0;bottom:0;background:rgba(0,0,0,0.5);z-index:1000;display:flex;align-items:center;justify-content:center';
   div.onclick = function(e) { if (e.target === this) this.remove(); };
   div.innerHTML = '<div style="background:#fff;border-radius:16px;padding:2rem;text-align:center;max-width:340px">' +
-    '<h3 style="margin-bottom:0.8rem;font-size:1.1rem;">请使用微信扫码支付</h3>' +
+    '<h3 style="margin-bottom:0.8rem;font-size:1.1rem;">用其他手机扫码支付</h3>' +
     '<div style="background:#f0fdfa;border-radius:8px;padding:0.8rem;margin-bottom:0.8rem;text-align:left">' +
       '<div style="font-size:0.85rem;color:var(--text-secondary);margin-bottom:0.3rem">肠道菌群基因检测</div>' +
       '<div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:0.3rem">' +
@@ -536,7 +536,7 @@ function showQrCode(codeUrl, orderNo) {
     '<div style="width:200px;height:200px;margin:0 auto 0.8rem;display:flex;align-items:center;justify-content:center;border-radius:8px;overflow:hidden">' +
       '<img src="/api/payment/qrcode?text=' + encodeURIComponent(codeUrl) + '" alt="支付二维码" style="width:200px;height:200px">' +
     '</div>' +
-    '<p style="font-size:0.8rem;color:#999">' + (isWechatBrowser() ? '请截图保存二维码 → 打开微信扫一扫 → 从相册选择' : '打开微信「扫一扫」完成支付') + '</p>' +
+    '<p style="font-size:0.8rem;color:#999">请用其他手机微信扫码完成支付</p>' +
     '<button onclick="this.closest(\'div[style]\').remove()" style="margin-top:0.8rem;padding:0.5rem 2rem;border:1px solid #e2e8f0;border-radius:8px;background:#fff;cursor:pointer">取消支付</button>' +
     '</div>';
   document.body.appendChild(div);

web/product-intro/kangen-water.html

@@ -550,7 +550,7 @@ function showQrCode(codeUrl, orderNo, productName, amount) {
   div.style.cssText = 'position:fixed;top:0;left:0;right:0;bottom:0;background:rgba(0,0,0,0.5);z-index:1000;display:flex;align-items:center;justify-content:center';
   div.onclick = function(e) { if (e.target === this) this.remove(); };
   div.innerHTML = '<div style="background:#fff;border-radius:16px;padding:2rem;text-align:center;max-width:340px">' +
-    '<h3 style="margin-bottom:0.8rem;font-size:1.1rem;">请使用微信扫码支付</h3>' +
+    '<h3 style="margin-bottom:0.8rem;font-size:1.1rem;">用其他手机扫码支付</h3>' +
     '<div style="background:#f0fdfa;border-radius:8px;padding:0.8rem;margin-bottom:0.8rem;text-align:left">' +
       '<div style="font-size:0.85rem;color:var(--text-secondary);margin-bottom:0.3rem">' + productName + '</div>' +
       '<div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:0.3rem">' +
@@ -566,7 +566,7 @@ function showQrCode(codeUrl, orderNo, productName, amount) {
     '<div style="width:200px;height:200px;margin:0 auto 0.8rem;display:flex;align-items:center;justify-content:center;border-radius:8px;overflow:hidden">' +
       '<img src="/api/payment/qrcode?text=' + encodeURIComponent(codeUrl) + '" alt="支付二维码" style="width:200px;height:200px">' +
     '</div>' +
-    '<p style="font-size:0.8rem;color:#999">' + (typeof isWechatBrowser === 'function' && isWechatBrowser() ? '请截图保存二维码 → 打开微信扫一扫 → 从相册选择' : '打开微信「扫一扫」完成支付') + '</p>' +
+    '<p style="font-size:0.8rem;color:#999">请用其他手机微信扫码完成支付</p>' +
     '<button onclick="this.closest(\'div[style]\').remove()" style="margin-top:0.8rem;padding:0.5rem 2rem;border:1px solid #e2e8f0;border-radius:8px;background:#fff;cursor:pointer">取消支付</button>' +
     '</div>';
   document.body.appendChild(div);