Overhaul setup wizard help pages

the context can now override a virtual method named `CreateHelpContent` which the setup wizard system will automatically try to use when you use the generic overload taking a generic context type. If the return is null, it skips setting entirely (the default impl is null)

additionally made the discord join link a button with code copied from the about window, and made it centered at the bottom.

src/Ryujinx/UI/SetupWizard/RyujinxSetupWizard.cs

@@ -1,14 +1,22 @@
 using Avalonia;
 using Avalonia.Controls.Notifications;
+using Avalonia.Media.Imaging;
+using Avalonia.Styling;
+using Avalonia.Threading;
+using Gommon;
 using Ryujinx.Ava.Common.Locale;
 using Ryujinx.Ava.Systems.Configuration;
 using Ryujinx.Ava.UI.Helpers;
 using Ryujinx.Ava.UI.SetupWizard.Pages;
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Runtime.CompilerServices;
 using System.Threading.Tasks;
 
 namespace Ryujinx.Ava.UI.SetupWizard
 {
-    public class RyujinxSetupWizard(RyujinxSetupWizardWindow wizardWindow, bool overwriteMode)
+    public class RyujinxSetupWizard : IDisposable, INotifyPropertyChanged
     {
         private bool _configWasModified;
 
@@ -18,12 +26,12 @@ namespace Ryujinx.Ava.UI.SetupWizard
 
         public async Task Start()
         {
-            NotificationManager = wizardWindow.CreateNotificationManager(
+            NotificationManager = _window.CreateNotificationManager(
                 // I wanted to do bottom center but that...literally just shows top center? Okay.
                 // Fuck it, weird window height hack to do it instead.
                 // 120 is not exact, just a random number. Looks fine though.
                 NotificationPosition.TopCenter,
-                margin: new Thickness(0, wizardWindow.Height - 120, 0, 0)
+                margin: new Thickness(0, _window.Height - 120, 0, 0)
             );
 
             RyujinxSetupWizardWindow.IsOpen = true;
@@ -49,13 +57,38 @@ namespace Ryujinx.Ava.UI.SetupWizard
                 ConfigurationState.Instance.ToFileFormat().SaveConfig(Program.GlobalConfigurationPath);
 
             NotificationManager = null;
-            wizardWindow.Close();
+            _window.Close();
             RyujinxSetupWizardWindow.IsOpen = false;
         }
 
+        public Bitmap DiscordLogo
+        {
+            get;
+            set => SetField(ref field, value);
+        }
+
+        private void Ryujinx_ThemeChanged()
+        {
+            Dispatcher.UIThread.Post(() => UpdateLogoTheme(ConfigurationState.Instance.UI.BaseStyle.Value));
+        }
+
+        private const string LogoPathFormat = "resm:Ryujinx.Assets.UIImages.Logo_{0}_{1}.png?assembly=Ryujinx";
+
+        private void UpdateLogoTheme(string theme)
+        {
+            bool isDarkTheme = theme == "Dark" ||
+                               (theme == "Auto" && RyujinxApp.DetectSystemTheme() == ThemeVariant.Dark);
+
+            string themeName = isDarkTheme ? "Dark" : "Light";
+
+            DiscordLogo = LoadBitmap(LogoPathFormat.Format("Discord", themeName));
+        }
+
+        private static Bitmap LoadBitmap(string uri) => new(Avalonia.Platform.AssetLoader.Open(new Uri(uri)));
+
         private async ValueTask<bool> SetupKeys()
         {
-            if (overwriteMode || !RyujinxApp.MainWindow.VirtualFileSystem.HasKeySet)
+            if (_overwrite || !RyujinxApp.MainWindow.VirtualFileSystem.HasKeySet)
             {
                 Retry:
                 bool result = await NextPage()
@@ -75,7 +108,7 @@ namespace Ryujinx.Ava.UI.SetupWizard
 
         private async ValueTask<bool> SetupFirmware()
         {
-            if (overwriteMode || !HasFirmware)
+            if (_overwrite || !HasFirmware)
             {
                 if (!RyujinxApp.MainWindow.VirtualFileSystem.HasKeySet)
                 {
@@ -99,13 +132,54 @@ namespace Ryujinx.Ava.UI.SetupWizard
             return true;
         }
 
-        private SetupWizardPage FirstPage() => new(wizardWindow.WizardPresenter, this, isFirstPage: true);
+        private SetupWizardPage FirstPage() => new(_window.WizardPresenter, this, isFirstPage: true);
 
-        private SetupWizardPage NextPage() => new(wizardWindow.WizardPresenter, this);
+        private SetupWizardPage NextPage() => new(_window.WizardPresenter, this);
 
         public void SignalConfigModified()
         {
             _configWasModified = true;
         }
+
+        private readonly RyujinxSetupWizardWindow _window;
+        private readonly bool _overwrite;
+
+        public RyujinxSetupWizard(RyujinxSetupWizardWindow wizardWindow, bool overwriteMode)
+        {
+            _window = wizardWindow;
+            _overwrite = overwriteMode;
+
+            if (Program.PreviewerDetached)
+            {
+                UpdateLogoTheme(ConfigurationState.Instance.UI.BaseStyle);
+                RyujinxApp.ThemeChanged += Ryujinx_ThemeChanged;
+            }
+        }
+
+        public void Dispose()
+        {
+            RyujinxApp.ThemeChanged -= Ryujinx_ThemeChanged;
+
+            DiscordLogo.Dispose();
+
+            Console.WriteLine("disposed");
+
+            GC.SuppressFinalize(this);
+        }
+
+        public event PropertyChangedEventHandler PropertyChanged;
+
+        protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
+
+        protected bool SetField<T>(ref T field, T value, [CallerMemberName] string propertyName = null)
+        {
+            if (EqualityComparer<T>.Default.Equals(field, value)) return false;
+            field = value;
+            OnPropertyChanged(propertyName);
+            return true;
+        }
     }
 }