Add suitability status and transfer request to the built-in route

1. Added an API to read availability status from MediaRoute2Info
2. Supported transfer reason and uid of a calling processes in
   RoutingSessionInfo
3. Implemented a system property to setup the built-in suitability
   status
4. All changes are hidden under the dedicated feature flag

There is still pending line of work:
- Modify SysUI to provide transfer meta-information from the Output
  Switcher
- Investigate whether it is necessary to propagate this
  meta-information to the user-defined routes

Bug: b/279555229
Test: mp droid
Change-Id: I0a45e52f7cc7b7158719cdaba0752a312e5d6543