The optimistically_confirmed_bank_tracker module implements a threaded service to track the
most recent optimistically confirmed bank for use in rpc services, and triggers gossip
subscription notifications.
This module also supports notifying of slot status for subscribers using the SlotNotificationSender.
It receives the BankNotification events, transforms them into SlotNotification and sends them via
SlotNotificationSender in the following way:
BankNotification::OptimisticallyConfirmed โ> SlotNotification::OptimisticallyConfirmed
BankNotification::Frozen โ> SlotNotification::Frozen
BankNotification::NewRootedChain โ> SlotNotification::Root for the roots in the chain.
The TransactionStatusService receives executed transactions and creates
transaction metadata objects to persist into the Blockstore and optionally
broadcast over geyser. The service also records block metadata for any
frozen banks it receives.