chore: Filter and Relay should be compliant with IReceiver

[danisharora099]

With work on #1682, we are changing the Filter API -- this also impacts the IRelay API as both of these protocol implementations are expected to be compliant with our IReceiver interface.

In the interest of keeping the PR straightforward, only Filter refactor is addressed with #1682.

This issue aims to track the work around Relay, and necessary updates to the IReceiver API.

This was discussed in the PM meeting (#1683 (comment)).

Acceptance Criteria:

• update Relay protocol, in a similar structure as Filter
• emsure Filter and Relay are compliance with IReceiver (update IReceiver accordingly)
• update & ensure these protocol implementations work with toAsyncIterator
  • un-skip the Util: toAsyncIterator: Filter test

[chair28980]

Depends on #1683