Add the Cross-Stage FDM menu item to the profile menu for mobile

What does this MR do and why?

Adds the link directing certain users to the cross-stage feature discovery moment to the profile menu for narrow (a.k.a. mobile) screen sizes (when the header help dropdown is not rendered).

Screenshots or screen recordings

TBD

How to set up and validate locally

TBD

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #353184 & #348494 (closed)