Add Assistant button to dictionary pop-up menu

[Rogerthis]

I would like to be able to access the Assistant from the pop-up dictionary menu.

At present, there is an option to go to Dictionary (AI), but from there, it is not possible to move into Assistant.
In Assistant: Dictionary, the bottom-left button shows Switch Model, while in the other Assistant views the bottom-left button is Ask Another.

This means that to return to Assistant I have to exit the dictionary pop-up menu, which interrupts the flow.

A similar change was proposed in the AskGPT project: drewbaumann#31