Improve deploy key and webhook URL display

- Format deploy key with comment: upaas-<date>-<vhost>
- Build webhook URL using Host header with https://

templates/app_detail.html

@@ -50,7 +50,7 @@
         <h2 class="section-title mb-4">Deploy Key</h2>
         <p class="text-sm text-gray-500 mb-3">Add this SSH public key to your repository as a read-only deploy key:</p>
         <div class="copy-field">
-            <code id="deploy-key" class="copy-field-value text-xs">{{.App.SSHPublicKey}}</code>
+            <code id="deploy-key" class="copy-field-value text-xs">{{.DeployKey}}</code>
             <button
                 type="button"
                 data-copy-target="deploy-key"