feat: reference implementation for Store v3 protocol

[jm-clius]

Problem

This feature forms the reference implementation part of Waku Research's new Store protocol proposal.
The overall research task is tracked in waku-org/research#81
The parallel RFC proposal is documented in vacp2p/rfc#665

Acceptance criteria

• functioning reference implementation of docs: introduce new store v3 protocol vacp2p/rfc#665
• the current Store protocol (/vac/waku/store/2.0.0-beta4) must be mounted in parallel to allow backwards compatibility

cc @SionoiS

[SionoiS]

PR #2431