This is an encapsulation of the common work done by all of our
single-client IPC servers on startup:
1. Create a Core::LocalSocket, taking over an accepted fd.
2. Create an application-specific ClientConnection object,
wrapping the socket.
It's not a huge change in terms of lines saved, but I do feel that it
improves expressiveness. :^)
These ones all manage their storage internally, whereas the WebContent
and ImageDecoder ones require the caller to manage their lifetime. This
distinction is not obvious to the user without looking through the code,
so an API that makes this clearer would be nice.
With this change, System::foo() becomes Core::System::foo().
Since LibCore builds on other systems than SerenityOS, we now have to
make sure that wrappers work with just a standard C library underneath.
Since applications using Core::EventLoop no longer need to create a
socket in /tmp/rpc/, and also don't need to listen for incoming
connections on this socket, we can remove a whole bunch of pledges!
The WebSocket service isolates communication with a WebSocket to its
own isolated process. Similar to other isolating services, it has its
own user and group.
