Distribute SafeSky data through WS.
clients
+---+ +---+
WS | | | |
+------------+ +------------------------+ ------> | | | |
| SafeSky | 4 sec | safesky-ws | +---+ +---+
| + <----- +------------------------+ ------>
| REST API | | filtering for viewport | +---+ +---+
+------------+ +------------------------+ ------> | | | |
| | | |
+---+ +---+
TBA