Add option to filter newly loaded data in `initSafetyGraphics()`

[jwildfire]

Allow users to filter any data set right after it's loaded in the initSafetyGraphics() app. This is definitely nice to have, but can probably wait until after v2.

cc: @sibyllwangxxxx @xni7

[jwildfire]

Not sure i remember the use case here, seems like it would be easy enough to filter data before initializing app if needed. Closing unless someone can add more detail.