Document baseURI and contractURI fields for sdk.nft.deploy

[bobwith2bees]

This information was previously documented, now I can no longer find it without using the Wayback machine.

Using the example app from the SDK (https://github.com/rarible/example):

Please provide guidance on how to use these fields. I found a reference in the Quickstart but it also looks like placeholder data:
https://docs.rarible.org/getting-started/quick-start/#create-collection

Bonus points to let me know if the yellow fields are the same - and what that means. The example code appears to ignore it when deploying.