Refactor: Reorganize project structure by moving core components into dedicated directories and introducing new configuration and API models.

Configuration/ConfigManager.cs

@@ -0,0 +1,40 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+using Toak.Serialization;
+
+namespace Toak.Configuration;
+public static class ConfigManager
+{
+    private static readonly string ConfigDir = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), ".config", "toak");
+    private static readonly string ConfigPath = Path.Combine(ConfigDir, "config.json");
+
+    public static ToakConfig LoadConfig()
+    {
+        if (!File.Exists(ConfigPath))
+        {
+            return new ToakConfig();
+        }
+
+        try
+        {
+            var json = File.ReadAllText(ConfigPath);
+            return JsonSerializer.Deserialize(json, AppJsonSerializerContext.Default.ToakConfig) ?? new ToakConfig();
+        }
+        catch (Exception)
+        {
+            return new ToakConfig();
+        }
+    }
+
+    public static void SaveConfig(ToakConfig config)
+    {
+        if (!Directory.Exists(ConfigDir))
+        {
+            Directory.CreateDirectory(ConfigDir);
+        }
+
+        var json = JsonSerializer.Serialize(config, AppJsonSerializerContext.Default.ToakConfig);
+        File.WriteAllText(ConfigPath, json);
+    }
+}