MetadataListener: only remove corresponding callbacks

Previously, calling unregister would unregister all the listener from
all apps on a specific device, instead of only the listener that
correspond to the caller

Also move to a remote callback list to not leak binder when app is dying

Bug: 362513490
Test: m Bluetooth
Flag: None applying remote callback pattern
Change-Id: Icb96867099768d7788ca4910894e5b268a38974e