Creating signal callbacks generates invalid C# code

[rzubek]

Godot version

v4.1.1.stable.mono.official [bd6af8e]

System information

Godot v4.1.1.stable.mono - Windows 10.0.22621 - Vulkan (Compatibility) - Intel(R) Iris(R) Xe Graphics (Intel Corporation; 30.0.101.3118) - 12th Gen Intel(R) Core(TM) i7-1255U (12 Threads)

Issue description

Code generation for signals generates invalid C# code.

While the generated function stub is fine, it's placed at the very end of the .cs file, outside of the class definition.

Steps to reproduce

1. I have set up Visual Studio 2022 as the external editor, not sure if that matters.
2. Follow the official "step by step" guide to this step: https://docs.godotengine.org/en/stable/getting_started/step_by_step/signals.html#connecting-a-signal-in-the-editor - however, follow C# instructions instead of GDScript instructions.
3. Create a new receiver method as described in the tutorial:
   
4. Observe that the generated code is invalid: method definition lives outside of the class definition:
   

Expected result:
Method definition should be generated inside its respective class definition.

Minimal reproduction project

Follow the official "step by step" guide, the problem is visible in this step:
https://docs.godotengine.org/en/stable/getting_started/step_by_step/signals.html#connecting-a-signal-in-the-editor

[Chaosus]

Duplicate of #18721