Add type support

[Xinart]

Describe the bug

When the addon is downloaded it crashes when using Godot with GDScript strict typing mode.

To Reproduce

1. Active GDScript strict typing mode on Godot with the following settings setted

2. Download the Godot addon from the AssetLib

Expected behavior

The Output show this :
ERROR: res://addons/antialiased_line2d/antialiased_line2d.gd:8 - Parse Error: Identifier "AntialiasedLine2DTexture" not declared in the current scope.
ERROR: modules/gdscript/gdscript.cpp:3041 - Failed to load script "res://addons/antialiased_line2d/antialiased_line2d.gd" with error "Parse error".
ERROR: res://addons/antialiased_line2d/antialiased_polygon2d.gd:18 - Parse Error: Identifier "AntialiasedLine2DTexture" not declared in the current scope.
ERROR: modules/gdscript/gdscript.cpp:3041 - Failed to load script "res://addons/antialiased_line2d/antialiased_polygon2d.gd" with error "Parse error".
ERROR: res://addons/antialiased_line2d/antialiased_regular_polygon2d.gd:21 - Parse Error: Identifier "AntialiasedLine2DTexture" not declared in the current scope.
ERROR: modules/gdscript/gdscript.cpp:3041 - Failed to load script "res://addons/antialiased_line2d/antialiased_regular_polygon2d.gd" with error "Parse error".

Software used

OS: Windows 11
Godot: Version 4.5.1

[Calinou]

Addons are normally ignored by default for GDScript warnings (including warnings turned into errors):

That said, I'm open to a PR that adds type hints everywhere so that the untyped declaration warning is no longer emitted.