Rework AbstractCodecFactory.codecFor()

AbstractCodecFactory performs leafref resolution based on an 'S extends TypeAware & SchemaNode' – leading to a call to SchemaContextUtil.getBaseTypeForLeafRef().

YANGTOOLS-1229 deals with properly moving that method to SchemaInferenceStack, effectively resulting in codecFor() requiring it.
Since SchemaInferenceStack is a mutable structure, we do not want to deal with its lifecycle, but rather have callers of codecFor() provide a resolution callback – and they will provide an appropriate SchemaInferenceStack-based implementation.