Improve startup HTTP checks so app is not blocked in no-outbound environments

src/ServiceControl.Config/Framework/RaygunFeedBack.cs

@@ -138,7 +138,7 @@ async Task<bool> TryInitializeRaygunClientWithCredentials(ICredentials? credenti
         readonly Guid trackingId;
         readonly RaygunSettings raygunSettings = new() { ApiKey = "zdm49nndHCXZ3NVzM8Kzug==" };
 
-        const string RaygunUrl = "https://raygun.io";
+        const string RaygunUrl = "https://raygun.com";
 
         sealed class Feedback(string message) : Exception(message);
     }

src/ServiceControl.Config/UI/Shell/ShellViewModel.cs

@@ -94,7 +94,7 @@ protected override async Task OnActivate()
         {
             await base.OnActivate();
 
-            await CheckForUpdates();
+            BeginCheckForUpdates();
         }
 
         public async Task RefreshInstances()
@@ -121,27 +121,42 @@ void LoadAppVersion()
             AppVersion = Constants.CurrentVersion;
         }
 
-        async Task CheckForUpdates()
+        void BeginCheckForUpdates()
         {
-            // Get the lates upgradble version based on the current version
-            // get the json version file from https://s3.us-east-1.amazonaws.com/platformupdate.particular.net/servicecontrol.txt
-
-            var availableUpgradeRelease = await VersionCheckerHelper.GetLatestRelease(AppVersion);
-
-            if (availableUpgradeRelease.Version == AppVersion)
-            {
-                UpdateAvailable = false;
-            }
-            else
+            updateCheckTask = Task.Run(async () =>
             {
-                AvailableUpgradeReleaseLink = availableUpgradeRelease.Assets.FirstOrDefault().Download.ToString();
-                UpdateAvailableText = $"v{availableUpgradeRelease.Version} - Update Available";
-                UpdateAvailable = true;
-            }
-
-            NotifyOfPropertyChange(nameof(UpdateAvailable));
+                NotifyOfPropertyChange(nameof(IsCheckingForUpdate));
+                try
+                {
+                    // Get the lates upgradeable version based on the current version
+                    // get the json version file from https://s3.us-east-1.amazonaws.com/platformupdate.particular.net/servicecontrol.txt
+
+                    var availableUpgradeRelease = await VersionCheckerHelper.GetLatestRelease(AppVersion);
+
+                    if (availableUpgradeRelease.Version == AppVersion)
+                    {
+                        UpdateAvailable = false;
+                    }
+                    else
+                    {
+                        AvailableUpgradeReleaseLink = availableUpgradeRelease.Assets.FirstOrDefault().Download.ToString();
+                        UpdateAvailableText = $"v{availableUpgradeRelease.Version} - Update Available";
+                        UpdateAvailable = true;
+                    }
+
+                    NotifyOfPropertyChange(nameof(UpdateAvailable));
+                }
+                finally
+                {
+                    updateCheckTask = null;
+                    NotifyOfPropertyChange(nameof(IsCheckingForUpdate));
+                }
+            });
         }
 
+        public bool IsCheckingForUpdate => updateCheckTask is not null;
+
+        Task updateCheckTask;
         readonly ListInstancesViewModel listInstances;
         readonly NoInstancesViewModel noInstances;
     }

src/ServiceControl.Config/UI/Shell/VersionCheckerHelper.cs

@@ -43,11 +43,12 @@ static async Task<List<Release>> GetVersionInformation()
             }
         }
 
-        static readonly HttpClient httpClient = new HttpClient(new HttpClientHandler
+        static readonly HttpClient httpClient = new(new HttpClientHandler
         {
             AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate
         })
         {
+            Timeout = TimeSpan.FromSeconds(30),
             DefaultRequestHeaders =
             {
                 Accept =