* Extract the common part into HearingAidHelper.
* Remove abstract getHearingDevice(). Change to get the hearing device when needed.
* Move several classes from Bluetooth into Accessibility
Bug: 281783079
Test: make RunSettingsRoboTests ROBOTEST_FILTER="(HearingDeviceAudioRoutingBasePreferenceControllerTest|AccessibilityHearingAidPreferenceControllerTest|HearingAidHelperTest|HearingAidAudioRoutingPreferenceControllerTest|HearingDeviceCallRoutingPreferenceControllerTest)"
Change-Id: I79049107409b7086c6dcc8d48a6323e171ed1535
* Setup basic xml for hearing device controls and audio output in bluetooth detail device page.
* Use same PreferenceCategory with spatial audio and rename to
`feature_controls_group`
Bug: 237625815
Test: make RunSettingsRoboTests ROBOTEST_FILTER=BluetoothDetailsHearingDeviceControlsControllerTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=BluetoothDetailsAudioRoutingControllerTest
Change-Id: Ibe71757b53b9d65c6ab6efa1053d035e78882b68