Right now if you open Zed, and we deserialize an agent that's behind a
feature flag (e.g. CC), we don't restore it because the feature flag
check hasn't happened yet at the time we're deserializing (due to auth
not having finished yet).

This is a simple fix: assume that if you had serialized it in the first
place, you must have had the feature flag enabled, so go ahead and
reopen it for you.

Release Notes:

- N/A