[MR2] Improve transferTo handling during broadcast

1. add isBtRoute and skip transferAction for BT device during broadcast
2. move the setActive for classic BT device to stopBroadcast and no need
   to removePreferredDeviceForStrategy

Bug: 438156758
Test: atest AudioManagerRouteControllerTest
Flag: com.android.media.flags.enable_output_switcher_personal_audio_sharing
Change-Id: If1854425e2d8a62ca882bcb3f6edcb99f84792d0