fix(upgrade): wait for new version before showing success

Expose the running Coolify version on /api/health and only treat an upgrade as complete once that version meets the target. Parse upgrade status in a shared service, start the update after the Livewire response, and keep polling when the instance is still on the old version.

tests/Feature/HealthcheckVersionHeaderTest.php

@@ -0,0 +1,22 @@
+<?php
+
+use App\Http\Controllers\Api\OtherController;
+use Illuminate\Http\Request;
+
+it('adds the running version header on the healthcheck response', function () {
+    config(['constants.coolify.version' => '4.3.1']);
+
+    $response = (new OtherController)->healthcheck(Request::create('/api/health', 'GET'));
+
+    expect($response->getContent())->toBe('OK')
+        ->and($response->headers->get('X-Coolify-Version'))->toBe('4.3.1');
+});
+
+it('exposes the running Coolify version on the public health endpoint', function () {
+    config(['constants.coolify.version' => '4.3.1']);
+
+    $this->get('/api/health')
+        ->assertSuccessful()
+        ->assertSee('OK')
+        ->assertHeader('X-Coolify-Version', '4.3.1');
+});