Client: new extra BeaconComponent logic:

• Construct AABB for beam
• Check if player is in the beam, if yes -> notify server

Server: listen for enter beam event:

• (Optional to get it working, but should be implemented) Check if player is actually in the beam
• Enter player into the network

Implemented server-side check in e3731c8
From testing it doesn't seem like there's too much strain on the server side (tested with 30 players and 100 beacons), so the client check could probably be removed altogether.

Leaving this open for now:
This could (and should) have server-side only implementation that can be controlled via config. Unless there's lots of players, it shouldn't be a strain on the server.