[DRAFT] Feat: Add custom scope and collection to replication

[alexbran8]

Description

This PR adds support for syncing and replicating from a custom scope and collection.
This enables replication from databases that contain multiple scopes and collections, not just the _default ones.

Changes

• updated request URL construction to include scope and collection as part of the database path
  (e.g. myAppSync.orders.data/_changes)
• defaulted scope and collection to _default when not provided

Not covered stuff

• tests (happy to add updates if could be helped with a bit more context)

Test cases

• replication/sync from custom scope and collection
• replication from default scope and collection