Implement folding for `.tree` files

[PraneshASP]

Ref: https://x.com/lucasmanuel_eth/status/1737466723568128394

This is awesome but I'm still unable to minimize at each level, any chance we can add that feature @0xasp_ good sir? https://t.co/I6EkWHYL17 pic.twitter.com/JlN319iVIv

— Lucas Manuel (@lucasmanuel_eth) December 20, 2023

[PaulRBerg]

I've just bumped into this - I wanted to be able to fold this subsection of our withdraw tree but I couldn't do it:

[PraneshASP]

yeah I was facing some issues as well. VSCode provides inbuilt support for folding codeblocks, but it doesn't work well for tree files. I started looking into it a while back, but didn't make much progress as it got quite complex than I anticipated. Will get back to it in a week or 2.