Allow switching projects by clicking the project name when creating a new thread

[xixixao]

When creating a new thread, the main panel displays the <current project's name> / New thread, but clicking the name does nothing.

It would be convenient to make the project name clickable and open the project switcher directly, without having to navigate through the sidebar.

This is not about less clicks, I don't even need this feature, but I've seen multiple new people to T3 code and people on twitter complaining about this (maybe it's a pattern they're used to from PyCharm). Unless there's something else we plan for this click to do, opening the project selector makes sense to me.

[dale-french]

+1. I keep clicking the project name in the project / thread breadcrumb and expecting the project picker.