[Bug] Nested subagents lost when switching to agents view and returning to session

Question

**Bug Description**
I had an active session with (nested) subagents. I accidentally pressed the left arrow button which opened the agents view and when I tried to re-enter the active session, the nested subagents were gone and it tried to respawn them by reacting to the previous prompt - as if the active session never progressed. I have no idea where the subagents went and what happened to all the progress! They're just gone as if they never existed.

**Environment Info**
- Platform: darwin
- Te