admin: Tags-list photo thumbnail (null when no photo — fixes empty src), edit-form photo preview (blade view), 'View live page' row action; owner: 'View the live tag page' link on edit

frontend/templates/tag-edit.html

@@ -31,6 +31,7 @@
         <div>
           <input type="file" name="photo" accept="image/*" class="text-sm" onchange="var f=this.files[0]; if(f){ var p=document.getElementById('photo-preview'); p.classList.remove('hidden'); var r=new FileReader(); r.onload=function(e){ p.src=e.target.result; }; r.readAsDataURL(f); }">
           <p class="mt-1 text-xs text-stone-500">Choose a photo and press Save. If you choose nothing, the current photo is kept.</p>
+      <p class="mt-2"><a href="/t/{{.Data.TagCode}}" target="_blank" rel="noopener" class="text-xs text-amber-600 hover:underline">👁 View the live tag page</a></p>
         </div>
       </div>
     </div>