Added Satellite Messaging APIs.

The following apis are added in this CL:
- registerForSatelliteStateChange()
- unregisterForSatelliteStateChange()
- registerForSatelliteDatagram()
- unregisterForSatelliteDatagram()
- getPendingSatelliteDatagrams()

Bug: 260896985
Test: atest SatelliteManagerTest
Change-Id: Iba46e8f453faa7d6f75802c71f8309e3c14e22a2