v0.238.0: the page follows the update, and a held app offers no way to start it (update arc slice 4 Part 4)

No behaviour change on the box — the surface only.

- Frissítés follows the job: the button shows the phase label (polling GET /api/stacks/{name}
  every 3 s) and the page reloads when updating goes false.
- An updating card offers no lifecycle button; a held card (failed update OR failed restore) shows
  the hold sentence with a Mentések link and nothing that would start it; a failed update that held
  nothing shows its sentence above the buttons. app_info shows the same three notices.
- The updating/held checks run BEFORE isOperational, which counts `restarting` as operational — how
  the 2026-09-01 spike saw a green Frissítés beside a crash loop. Pinned with StateRestarting
  fixtures; red-proofed by moving the checks after it (both tests fail).
- No new CSS, no version number.

Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/web/templates/layout.html

@@ -284,6 +284,13 @@
                 btn.classList.remove('loading');
                 return;
             }
+            // Slice 4: an update is ACCEPTED, not finished (HTTP 202). Follow its phases on this
+            // button until the box says it is done or failed — never reload into a page that still
+            // shows the old state as if nothing were happening.
+            if (action === 'update') {
+                followUpdate(name, btn);
+                return;
+            }
             window.location.reload();
         } catch (err) {
             showAlert('Hálózati hiba: ' + err.message);
@@ -292,6 +299,19 @@
             btn.classList.remove('loading');
         }
     }
+    function followUpdate(name, btn) {
+        var started = Date.now();
+        var timer = setInterval(async function() {
+            if (Date.now() - started > 30 * 60 * 1000) { clearInterval(timer); window.location.reload(); return; }
+            try {
+                var r = await fetch('/api/stacks/' + name);
+                var d = await r.json();
+                if (!d.ok || !d.data) return;
+                if (d.data.update_phase_label) btn.textContent = d.data.update_phase_label;
+                if (!d.data.updating) { clearInterval(timer); window.location.reload(); }
+            } catch (e) {}
+        }, 3000);
+    }
     async function deleteOrphanStack(name) {
         var modal = document.createElement('div');
         modal.className = 'modal-overlay';