infra: Make Avalonia the default UI (#6375)

* misc: Move Ryujinx project to Ryujinx.Gtk3

This breaks release CI for now but that's fine.

Signed-off-by: Mary Guillemard <mary@mary.zone>

* misc: Move Ryujinx.Ava project to Ryujinx

This breaks CI for now, but it's fine.

Signed-off-by: Mary Guillemard <mary@mary.zone>

* infra: Make Avalonia the default UI

Should fix CI after the previous changes.

GTK3 isn't build by the release job anymore, only by PR CI.

This also ensure that the test-ava update package is still generated to
allow update from the old testing channel.

Signed-off-by: Mary Guillemard <mary@mary.zone>

* Fix missing copy in create_app_bundle.sh

Signed-off-by: Mary Guillemard <mary@mary.zone>

* Fix syntax error

Signed-off-by: Mary Guillemard <mary@mary.zone>

---------

Signed-off-by: Mary Guillemard <mary@mary.zone>

src/Ryujinx.Gtk3/UI/Widgets/UserErrorDialog.cs

@@ -0,0 +1,123 @@
+using Gtk;
+using Ryujinx.UI.Common;
+using Ryujinx.UI.Common.Helper;
+
+namespace Ryujinx.UI.Widgets
+{
+    internal class UserErrorDialog : MessageDialog
+    {
+        private const string SetupGuideUrl = "https://github.com/Ryujinx/Ryujinx/wiki/Ryujinx-Setup-&-Configuration-Guide";
+        private const int OkResponseId = 0;
+        private const int SetupGuideResponseId = 1;
+
+        private readonly UserError _userError;
+
+        private UserErrorDialog(UserError error) : base(null, DialogFlags.Modal, MessageType.Error, ButtonsType.None, null)
+        {
+            _userError = error;
+
+            WindowPosition = WindowPosition.Center;
+            SecondaryUseMarkup = true;
+
+            Response += UserErrorDialog_Response;
+
+            SetSizeRequest(120, 50);
+
+            AddButton("OK", OkResponseId);
+
+            bool isInSetupGuide = IsCoveredBySetupGuide(error);
+
+            if (isInSetupGuide)
+            {
+                AddButton("Open the Setup Guide", SetupGuideResponseId);
+            }
+
+            string errorCode = GetErrorCode(error);
+
+            SecondaryUseMarkup = true;
+
+            Title = $"Ryujinx error ({errorCode})";
+            Text = $"{errorCode}: {GetErrorTitle(error)}";
+            SecondaryText = GetErrorDescription(error);
+
+            if (isInSetupGuide)
+            {
+                SecondaryText += "\n<b>For more information on how to fix this error, follow our Setup Guide.</b>";
+            }
+        }
+
+        private static string GetErrorCode(UserError error)
+        {
+            return $"RYU-{(uint)error:X4}";
+        }
+
+        private static string GetErrorTitle(UserError error)
+        {
+            return error switch
+            {
+                UserError.NoKeys => "Keys not found",
+                UserError.NoFirmware => "Firmware not found",
+                UserError.FirmwareParsingFailed => "Firmware parsing error",
+                UserError.ApplicationNotFound => "Application not found",
+                UserError.Unknown => "Unknown error",
+                _ => "Undefined error",
+            };
+        }
+
+        private static string GetErrorDescription(UserError error)
+        {
+            return error switch
+            {
+                UserError.NoKeys => "Ryujinx was unable to find your 'prod.keys' file",
+                UserError.NoFirmware => "Ryujinx was unable to find any firmwares installed",
+                UserError.FirmwareParsingFailed => "Ryujinx was unable to parse the provided firmware. This is usually caused by outdated keys.",
+                UserError.ApplicationNotFound => "Ryujinx couldn't find a valid application at the given path.",
+                UserError.Unknown => "An unknown error occured!",
+                _ => "An undefined error occured! This shouldn't happen, please contact a dev!",
+            };
+        }
+
+        private static bool IsCoveredBySetupGuide(UserError error)
+        {
+            return error switch
+            {
+                UserError.NoKeys or
+                UserError.NoFirmware or
+                UserError.FirmwareParsingFailed => true,
+                _ => false,
+            };
+        }
+
+        private static string GetSetupGuideUrl(UserError error)
+        {
+            if (!IsCoveredBySetupGuide(error))
+            {
+                return null;
+            }
+
+            return error switch
+            {
+                UserError.NoKeys => SetupGuideUrl + "#initial-setup---placement-of-prodkeys",
+                UserError.NoFirmware => SetupGuideUrl + "#initial-setup-continued---installation-of-firmware",
+                _ => SetupGuideUrl,
+            };
+        }
+
+        private void UserErrorDialog_Response(object sender, ResponseArgs args)
+        {
+            int responseId = (int)args.ResponseId;
+
+            if (responseId == SetupGuideResponseId)
+            {
+                OpenHelper.OpenUrl(GetSetupGuideUrl(_userError));
+            }
+
+            Dispose();
+        }
+
+        public static void CreateUserErrorDialog(UserError error)
+        {
+            new UserErrorDialog(error).Run();
+        }
+    }
+}