Resolve "Add extra functionality for the top right Plus Button"

What does this MR do?

It extends the top right menu + button with context sensitive additional "New ..." Actions.

Are there points in the code the reviewer needs to double check?

Tests that were broken due to having suddenly 2 "New .." buttons

Screenshots

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #23603 (closed)