Sessions: Bring over Copilot status bar information

[bamurtaugh]

As various folks have raised, it likely makes sense to bring over the Copilot status bar icon's entitlements and usage information into Sessions.

Given the layout differences in Sessions vs VS Code, I wonder if it makes sense to put this information in the lower left of Sessions, part of the menu when a user clicks on their GitHub username? Another idea could be in the top right (by other button controls like the run actions / terminal / changes / open VS Code buttons).