[Task] Resolve TODOs in the rebased alpha

[itsyaasir]

Description

There are couple of outstanding TODOs from the rebased codebase.

To-do list

• add entries when identity_iota package is published to well-known networks.
• remove argument package_id and use EventFilter::MoveEventField to find the beacon event and thus the package id.
• authenticate the beacon event with though sender's ID.