docs(changelog): add v1.7.43-alpha entry covering async lifecycle + .23 retirement

Four release-note bullets describing the user-visible changes shipped
in this round:

- async-spawn install/update/uninstall (UI no longer freezes)
- phase-based install progress bar (Preparing through Finalizing)
- scanner kick post-install (Launch button appears immediately)
- .23 Hetzner VPS retired, .168 OVH promoted to Server 1 with
  auto-purge migration for existing nodes

Matches the tone of existing changelog entries: what changed from the
operator's perspective, not internal implementation detail.

neode-ui/src/views/settings/AccountInfoSection.vue

@@ -180,6 +180,19 @@ init()
               </button>
             </div>
             <div class="overflow-y-auto flex-1 min-h-0 space-y-6 pr-1">
+              <!-- v1.7.43-alpha -->
+              <div>
+                <div class="flex items-center gap-2 mb-3">
+                  <span class="text-xs font-mono px-2 py-0.5 rounded bg-orange-500/20 text-orange-300">v1.7.43-alpha</span>
+                  <span class="text-xs text-white/40">Apr 23, 2026</span>
+                </div>
+                <div class="space-y-3 text-sm text-white/80 pl-3 border-l border-white/10">
+                  <p>Installing, updating, and removing apps no longer freezes the UI. The backend now spawns the actual work in the background and returns immediately, so the progress bar starts moving right away instead of the whole page locking up for 30+ seconds while podman pulls an image.</p>
+                  <p>Install progress bar actually reflects reality now. It previously stayed at 0% until the very end because podman doesn't emit parseable progress when run without a TTY. Replaced byte-counting with seven clearly-labelled phases — Preparing, Pulling image, Creating container, Starting, Waiting for health, Finalizing, Done — each mapped to a fixed percentage so the bar only moves forward.</p>
+                  <p>Launch button now appears the moment an install finishes, instead of waiting up to 60 seconds for the next container scan. After a successful install or update, the backend kicks the scanner and waits for a fresh manifest to land before flipping the app to Running, so the UI always has real port and UI-route info by the time the card becomes clickable.</p>
+                  <p>Retired the decommissioned .23 Hetzner VPS mirror. New nodes default to OVH (146.59.87.168) as Server 1 and tx1138 as Server 2 for both system updates and the app registry. Existing nodes auto-purge any saved .23 entries on next load so they stop paying connection-timeout penalties against a dead host.</p>
+                </div>
+              </div>
               <!-- v1.7.42-alpha -->
               <div>
                 <div class="flex items-center gap-2 mb-3">