This moves communication and route matching for WebDriver endpoints into
LibWeb. This is to reduce the amount of duplication required to create a
WebDriver implementation for Ladybird.
In doing so, this introduces some cleanup of WebDriver handling. Routes
are now a compile-time array, and matching a route is nearly free of
allocations (we still allocate a Vector for parsed parameters). This
implementation also makes heavier use of TRY semantics to propagate
errors into one handler.
