Doc: Add C# instructions

doc/source/getting-started/c-sharp.rst

@@ -0,0 +1,67 @@
+.. _csharp:
+
+Using LimboAI with C#
+=====================
+
+Here's how you can use the module version with C# to write your tasks and states.
+
+1. Locate LimboAI NuGet package files.
+
+Each provided build comes with a GodotSharp folder, which has packages under
+"GodotSharp/Tools/nupkgs/". Note down the directory path; you'll need it in the next step.
+
+2. Add a local source for NuGet packages using the following command:
+
+.. code:: shell
+
+    dotnet nuget add source path/to/limboai/nupkgs --name LimboNugetSource
+
+3. Your C# project should be able to see LimboAI classes and compile.
+
+Regarding GDExtension, I can only confirm success with the module version and C#.
+Unfortunately, I haven't had any luck with the GDExtension version yet.
+If you've had success with GDExtension, please let me know via Discord or email.
+
+Creating custom tasks in C#
+---------------------------
+
+   **🛈 Note:** For more information, check out :ref:`creating custom tasks in GDScript <custom_tasks>`.
+
+You can use the following script template for custom tasks:
+
+.. code:: csharp
+
+    using Godot;
+    using System;
+
+    [Tool]
+    public partial class _CLASS_ : _BASE_
+    {
+        public override string _GenerateName()
+        {
+            return "_CLASS_";
+        }
+
+        public override void _Setup()
+        {
+        }
+
+        public override void _Enter()
+        {
+        }
+
+        public override void _Exit()
+        {
+        }
+
+        public override Status _Tick(double delta)
+        {
+            return Status.Success;
+        }
+
+        public override string[] _GetConfigurationWarnings()
+        {
+            return Array.Empty<string>();
+        }
+    }
+

doc/source/index.rst

@@ -43,6 +43,7 @@ the other any time. For more information on this topic, see :ref:`gdextension`.
    getting-started/custom-tasks
    getting-started/using-blackboard
    getting-started/gdextension
+   getting-started/c-sharp
    getting-started/featured-classes
 
 .. toctree::