Fix Vultr power controls for stopped instances

tests/Feature/VultrServerLifecycleTest.php

@@ -236,6 +236,23 @@ it('blocks action validation when Vultr instance is stopped', function () {
     ]);
 });
 
+it('shows Vultr power on button when stopped even if server was previously functional', function () {
+    $this->server->update([
+        'ip' => '1.2.3.5',
+        'vultr_instance_status' => 'stopped',
+    ]);
+    $this->server->settings->update([
+        'is_reachable' => true,
+        'is_usable' => true,
+        'force_disabled' => false,
+    ]);
+
+    expect($this->server->fresh()->isFunctional())->toBeTrue();
+
+    Livewire::test(Show::class, ['server_uuid' => $this->server->uuid])
+        ->assertSee('Power On');
+});
+
 it('starts a Vultr instance', function () {
     Http::fake([
         'https://api.vultr.com/v2/instances/instance-1/start' => Http::response([], 204),

tests/Unit/VultrServiceTest.php

@@ -136,3 +136,17 @@ it('finds an instance by IPv4 or IPv6', function () {
         ->and($service->findInstanceByIp('2001:db8::1')['id'])->toBe('instance-1')
         ->and($service->findInstanceByIp('1.2.3.4'))->toBeNull();
 });
+
+it('handles empty successful responses from Vultr API', function () {
+    Http::fake([
+        'https://api.vultr.com/v2/instances/instance-1/start' => Http::response(null, 204),
+        'https://api.vultr.com/v2/instances/instance-1' => Http::response(null, 204),
+    ]);
+
+    $service = new VultrService('fake-token');
+
+    expect($service->startInstance('instance-1'))->toBe([]);
+    $service->deleteInstance('instance-1');
+
+    Http::assertSentCount(2);
+});