Added checking for updates

Services/SettingsService.cs

@@ -0,0 +1,50 @@
+using System.IO;
+using System.Text.Json;
+
+namespace MossyUpdater.Services
+{
+    public class SettingsService : ISettingsService
+    {
+        private readonly string _settingsPath;
+
+        public SettingsService()
+        {
+            var appDataPath = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData);
+            var appFolder = Path.Combine(appDataPath, "MossyUpdater");
+            Directory.CreateDirectory(appFolder);
+            _settingsPath = Path.Combine(appFolder, "settings.json");
+        }
+
+        public async Task<AppSettings> LoadSettingsAsync()
+        {
+            try
+            {
+                if (!File.Exists(_settingsPath))
+                    return new AppSettings();
+
+                var json = await File.ReadAllTextAsync(_settingsPath);
+                var settings = JsonSerializer.Deserialize<AppSettings>(json);
+                return settings ?? new AppSettings();
+            }
+            catch
+            {
+                return new AppSettings();
+            }
+        }
+
+        public async Task SaveSettingsAsync(AppSettings settings)
+        {
+            try
+            {
+                var json = JsonSerializer.Serialize(settings, new JsonSerializerOptions 
+                { 
+                    WriteIndented = true 
+                });
+                await File.WriteAllTextAsync(_settingsPath, json);
+            }
+            catch
+            {
+            }
+        }
+    }
+}