This is a great endeavour. Recently I have been thinking about how to add syntax and metaprogramming extensions to programming languages without forking the compiler/interpreter. Source maps are needed there in order to have good editor support through e.g. an LSP server proxy. In researching it I was a bit let down I couldn't find too much research and specifications for the topic.
https://github.com/EpicGamesExt/raddebugger?tab=readme-ov-fi...
Stuff like this makes me believe open wins over closed in the end :)