refactor(UXAssist): harden ModFeatureRegistry

UXAssist/Common/ModFeatures/IModFeature.cs

@@ -1,10 +1,33 @@
 namespace UXAssist.Common.ModFeatures;
 
+/// <summary>
+/// Interface implemented by instance mod features registered with <see cref="ModFeatureRegistry"/>.
+/// All lifecycle methods are invoked by the registry in the order described below.
+/// </summary>
 public interface IModFeature
 {
+    /// <summary>
+    /// Called once when the mod is initialized.
+    /// </summary>
     void Init();
+
+    /// <summary>
+    /// Called once after initialization, when the mod should begin active behavior.
+    /// </summary>
     void Start();
+
+    /// <summary>
+    /// Called once when the mod is being shut down or re-initialized.
+    /// </summary>
     void Uninit();
+
+    /// <summary>
+    /// Called every frame for input handling. Should be lightweight.
+    /// </summary>
     void OnInputUpdate();
+
+    /// <summary>
+    /// Called every frame for general updates. Should be lightweight.
+    /// </summary>
     void OnUpdate();
 }