Agents: Update new session options for first time user

[bamurtaugh]

Testing #315532

• code-insiders --transient
• Sign into GitHub using the first overlay modal in VS Code
• Open Agents window
• ❓ I have some questions about this first page experience:

• I'm uncertain why my recent repos are surfaced in the list on the left but not in the workspace dropdown picker
• Should we surface more info (like the harness dropdown picker) to give users an idea of what they'll be able to do with the Agents window before selecting a workspace?

[sandy081]

I'm uncertain why my recent repos are surfaced in the list on the left but not in the workspace dropdown picker

Its a very good question. Probably the recent list in the picker should contain the workspace populated in sessions list.

[bamurtaugh]

Also reported by @alexdima in #317716