feat(system): model status, a named model gate and downloads as Activity jobs (#328, PR 1) (#365)

* feat(autotag): model status without paths, and a busy answer that names the operation

* feat(autotag): model downloads run as Activity jobs

* fix(autotag): keep each download route's error shape and harden the fake download

web/admin.html

@@ -1428,12 +1428,13 @@ No sentences, no commentary, no captions. Only tags. Keep length short but descr
                 <div class="w-full bg-pm-input rounded-full h-1.5">
                     <div id="downloadProgressBar" class="bg-pm-accent h-1.5 rounded-full transition-all duration-300" style="width: 0%"></div>
                 </div>
+                <p class="text-pm-secondary text-xs mt-2">The download continues in Activity.</p>
             </div>
 
             <div class="flex justify-center">
                 <button id="cancelDownloadBtn"
                         class="px-3 py-1.5 text-pm-error bg-transparent hover:bg-pm-error-tint border border-pm text-xs font-medium rounded-pm-sm transition-colors">
-                    Cancel
+                    Close
                 </button>
             </div>
         </div>