refactor: ♻️ 4.1 support

[KANAjetzt]

supersedes #441

Original PR Description:

Changes made:

• Removed typed for...in variables because Godot 4.1 doesn't support them
• Downgraded some .tres to format version 3, because format version 4 isn't supported in Godot 4.1
• Used custom function instead of type_string, which does not exist in Godot 4.1

I did a proper test in Godot 4.1 and encountered no issues.

I did not test in later versions of Godot, but I don't think there's anything here that could break.

Todos

• _ModLoaderModHookPreProcessor.fix_method_super() erases everything after the function body, leaving only the first function in a script.
  

  godot-mod-loader/addons/mod_loader/internal/mod_hook_preprocessor.gd

  Lines 313 to 317 in 7b36e32

  	func fix_method_super(method_name: String, func_body: RegExMatch, text: String) -> String:
  	return regex_super_call.sub(
  	text, "super.%s" % method_name,
  	true, func_body.get_start(), func_body.get_end()
  	)

• Change the ´.fix_method_super()` fix to use Regex.sub again, and just add the rest of the string back after sub replaced the super calls.

Todos

• Godot 4.2 Test (Tested with Dome Keeper)
• Godot 4.3 Test (Tested with flashit)