Sky: transmit body_orbit_tilt to client. (#13193)

This obsoletes the current client-side setting entirely. The server can
transmit the tilt to the client directly and will send 0.0f as default
value.

Co-authored-by: x2048 <codeforsmile@gmail.com>
Co-authored-by: sfan5 <sfan5@live.de>

src/server.cpp

@@ -1808,6 +1808,8 @@ void Server::SendSetSky(session_t peer_id, const SkyboxParams &params)
 				<< params.sky_color.night_sky << params.sky_color.night_horizon
 				<< params.sky_color.indoors;
 		}
+
+		pkt << params.body_orbit_tilt;
 	}
 
 	Send(&pkt);