Sign out should clear view with workflows and ask you to sign in again

Repro steps
1. Sign out of account
2. Can still see workflows
Note: Cannot manipulate anything, which is good.


Expectation:
I would expect that upon sign out that I should be returned to this view:

There are other extensions that do an action upon Sign Out like Git Lens.

It might be worth seeing how they work and how they hook into a sign out from VS Code and perform an action.

Start by reproducing the sign-out flow in the VS Code extension and inspect how it responds when the account is signed out. Compare the sign-out behavior with GitLens as suggested in the issue; done means signing out clears the workflows view and returns the user to a sign-in prompt.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.