[BUG] New fleets sometimes fail to update after registration

[samuelgrant]

Describe the bug
Sometimes when registering a new fleet, the background worker doesn't fetch fleet information, this includes the boss location and fleet members.

This can be solved by re-starting the server process. I believe this is being caused by dirty reads.

What I'd like to do to resolve this is much smaller read/write sequences, I believe this will also solve an issue with the database where the ESI tokens often get wiped. The suggestion would be to read a list of IDs for both fleets and pilots as appropriate, then read information about the specific pilots/fleets and quickly write asap.