fix: Adds command help, webpage, and fixes issues with other commands (#1669)

### Summary

- Fixes `[AdvancedSearch` being accessible by players 😱 
- Adds `[GenCommands` to generate the same commands html page on https://muo.gg/commands.
- Fixes `[helpinfo` so all commands properly show up!

> [!WARNING]  
> ### Developer Warning:
> Commands must now be registered in the `Configure` bootup phase.
> If a command is not registered early enough, it may not be available to systems like [helpinfo
> that cache their information.

> [!NOTE]  
> ### Developer Note:
> Various commands related to generating content have been changed to _Developer_ and above access level.

### Screenshots
<img width="673" alt="image" src="https://github.com/modernuo/ModernUO/assets/3953314/b105b5c9-5eb4-4ace-93ff-1bfb31e7132f">

<img width="547" alt="image" src="https://github.com/modernuo/ModernUO/assets/3953314/e97487e8-47a5-4aa7-89cc-9fe3deda584d">

Projects/Server/Utilities/Html.cs

@@ -14,6 +14,7 @@
  *************************************************************************/
 
 using System.Runtime.CompilerServices;
+using System.Text;
 
 namespace Server.Utilities;
 
@@ -45,4 +46,14 @@ public static class Html
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static string Center(this string text, string color, int size) => $"<BASEFONT COLOR={color} SIZE={size}><CENTER>{text}</CENTER></BASEFONT>";
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static string EscapeHtml(this string input) =>
+        new StringBuilder(input.Length).Append(input)
+            .Replace("<", "&lt;")
+            .Replace(">", "&gt;")
+            .Replace("&", "&amp;")
+            .Replace("\"", "&quot;")
+            .Replace("'", "&#39;")
+            .ToString();
 }