Follow-up to #46641.

In the PR linked above, I had introduced a dropdown that'd show up in the title bar when the workspace contained more than one project. Although that helped improve the multi-project use case, it created some quirky designs:

• The project dropdown and the recent project pickers looked too different from one another
• The transition between the 2 project case to the 1 project scenario, from the dropdown, was not great, because you'd be then seeing the bigger recent projects picker
• The workspace: switch project action was still reachable in the command palette even if you had one project in the workspace

So, what this PR does is essentially fixing all of this by consolidating it all in the Recent Projects picker. If you are in a multi-project scenario, the picker will display a section with all of the projects on the workspace allowing you to activate each one of them. The picker also looks simpler when you reach it by clicking on the project name in the title bar, as opposed to through the keybinding. I've then removed the project dropdown code as well as the action, given we don't need them anymore due to the consolidation. Lastly, I tackled the inconsistent wording used between "Folders", "Projects", and "Workspaces".

Here's the result:

• Code Reviewed
• Manual QA

Release Notes:

• Workspace: Improved the recent projects picker by making it also display active projects in case of a multi-project workspace.