Feature request: incorporate something like typechat to have nodes that transform data in typed ways

Currently we need to add prompts like...
```
return a comma separated list of each of the questions here: {q}
Be sure what you return is a comma separated list. Don't have quotes around the list.
```

This is hard to do, easy to mess up, and scattered across my chain...

i am suggesting you do something like
add a set of predefined (but editable) nodes that transform llm responses into lists, bools, sentiment, etc...

one such wa of doing this would be to use a lib like typechat https://github.com/microsoft/TypeChat
which really just adds consistent gunk to the context the ensure a consistent output form an llm