docs: document limits in string fields

[crodriguezvega]

Description

I will also update v7.6.x docs when #6670 is merged.

closes: #6666

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[DimitrisJim]

pr for issue 6666 is fire though 😄 we should also make sure to mention destinationMemo after forwarding. I leave it up to you to add here after the feature branch is merged to main or as a separate PR.

[crodriguezvega]

pr for issue 6666 is fire though 😄 we should also make sure to mention destinationMemo after forwarding. I leave it up to you to add here after the feature branch is merged to main or as a separate PR.

I think I prefer to add this one as part of #6608. I will add your comment to the issue so that we don't forget about it.