Offering to maintain this library

Hi,

From time to time, i need to transform json. I looked other solutions like https://jsonata.org/ but did not fit my needs

Today i found st.js and worked fine.

I'm willing to maintain this project, like merging fixes from forks (https://github.com/danielduarte/flowed-st#differences-compared-to-the-original) as well modernizing the code base and playground