The ping/pong orders are replaced with a dedicated
(and much smaller) Ping packet that is handled
directly in the client and server Connection wrappers.
This allows clients to respond when the orders are
processed, instead of queuing the pong order to be
sent in the next frame (which added an extra 120ms
of unwanted latency).
The ping frequency has been raised to 1Hz, and pings
are now routed through the server events queue in
preparation for the future dynamic latency system.
The raw ping numbers are no longer sent to clients,
the server instead evaluates a single ConnectionQuality
value that in the future may be based on more than
just the ping times.
The previous asynchronous approach did not work particularly well,
leading to large janks when switching to custom maps or opening the
mission browser.
This commit introduces two key changes:
* Rule loading for WorldActorInfo and PlayerActorInfo is made
synchronous, in preparation for the next commit which will
significantly optimize this path.
* The full ruleset loading, which is required for map validation,
is moved to the server-side and managed by a new ServerMapStatusCache.
The previous syntax check is expanded to include the ability to run
lint tests.
