#toolbar-item-user id can appear twice when user item also in secondary toolbar

Problem/Motivation

Because the secondary toolbar can include items also in the primary toolbar, the #toolbar-item-user id can appear twice on the same page which can lead to JS errors and results in basic accessibility scans failing.

There are other duplicate id problems that are best addressed in the gin_toolbar module, which will get its own issue, but this one is most easily addressed in the theme itself.

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes