Build and cache offline data when exporting a Godot project

[tjmclain]

• [ ] YarnProject cached program
• [ ] YarnProject string table
• [ ] ActionLibrary action info lists

[tjmclain]

Use EditorExportPlugin for this. https://docs.godotengine.org/en/stable/classes/class_editorexportplugin.html

[tjmclain]

Use TOOLS preprocessor tag to determine whether or not we're in the editor player. Engine.IsEditorHint only works in the editor, not the editor player

https://docs.godotengine.org/en/stable/tutorials/scripting/c_sharp/c_sharp_features.html#full-list-of-defines