[FEATURE]Use WebSocket

[zyxgad]

I suggest bluemap use WebSocket to get data, that will reduce many unnecessary web request. Of course, bluemap need keep http API to compatible with the old client

[roobscoob]

If this is to be implemented, please keep the HTTP fetch option as a persistent choice. (i.e. don't deprecate/remove it). When deploying BlueMap at scale (for example, as an interactive component displaying a static world on a website) HTTP fetches are much better, as tools exist to optimize the delivery of static content over HTTP. These same tools do not exist for WebSockets

[FinlayDaG33k]

Do note that if websockets are going to be used, we'd also need to implement RFC 7692 in order to use some compression.

[TBlueF]

There is currently no intend to use web-sockets for the map-tiles .. in my opinion, http-requests are perfectly fine for that :) The web-sockets would be for live-updates like player-markers