Type Alias BeforeClose 

pub type BeforeClose = Pin<Box<dyn Future<Output = Result<()>> + Send>>;

Work a close runs once the session is about to close: its checkpoint is verified and recorded, and its relay is not sealed yet. A daemon suspend stops the session’s sub-agents here, so a close that fails at its checkpoint leaves them running. When this fails, the close does not proceed: the session returns to its previous state with its relay unsealed.

Aliased Type

#[repr(transparent)]
pub struct BeforeClose { /* private fields */ }