codegen: add tree-sitter support

[maxnoe]

Would be very nice to have for editor integration

[mr-c]

Hello @maxnoe ; do any of these editor integration satisfy your needs? https://www.commonwl.org/tools/#editors

[mr-c]

https://tree-sitter.github.io/tree-sitter/creating-parsers/2-the-grammar-dsl.html