Rather than manually launching the SQLServer process, use SQLClient's
new functionality to launch the server just once for all Ladybird
instances. Quit the SQLServer process when it no longer has any
connected clients.
When Ladybird exits, SQLServer can get stuck spinning at 100% CPU after
the socket connection is closed. This changes the client to quit the
event loop when that disconnect happens to ensure that SQLServer is
properly destroyed.
This adds a SQLServer binary for Ladybird to make use of Serenity's SQL
implementation. This has to use the same IPC socket handling that was
used to make WebContent and WebDriver work out-of-process.
Unlike Serenity, Ladybird creates a new SQLServer instance for each
Ladybird instance. In the future, we should try to make sure there is
only one SQLServer instance at a time, and allow multiple Ladybird
instances to communicate with it.
