[#67799226] route POST :search -> :index
Merge 67799226-re-route to master

[Completes #67799226]
Add specs showing mongoid behaviour with updated_at
default serialize now EXCLUDES last_local_status

I greped all PADMA repos and haven't found explicit
usage of last_local_status.

On serialization of big collections including this field
by default was generating ~10s delay.
check_duplicates is not a serializable attribute