Tutorial on cross chain communication

[rahul-kothari]

We have a tutorial on how to write a token bridge aztec-nr contract

But we need an e2e tutorial that shows the solidity token portal, the typescript glue code, the aztec-nr token bridge + private/public flow.

I can work on the code + docs on the setup (is a bit involved). Will appreciate if someone else can write docs on how it all works -> could also be a great learning experience on how message passing works (in-depth) with all of the gotchas and quirks!

[catmcgee]

I'd love to work with you on this!