Add package metadata sync service

What does this MR do and why?

This MR implements the package metadata sync service. It's in charge of invoking the connector responsible for:

Issue context

The sync service is the main service facilitating the pulling of external data, invoking the loading in the database, and saving the last stored position.

MR context

There are several external components that are invoked by this service which are still in review:

• gcp connector (responsible for pulling data from gcp bucket); and offline/archive connector - ready for dev
• ingestion service (responsible for batch storage of supplied data in the database)

Related to #383722 (closed)