Implement renderer protocol for RequestWearables flow

[dalkia]

Description

We should implement the new renderer protocol into the Wearable retrieve flow. Having the ability to use protobuf and streams will allow us to stop using the long json string, which produced a crash for users with many wearables.

We need to have a retro-compatible solution with the current web interface flow. A good reference is the new friend request flow, which uses a proxy bridge and a feature flag to decide which flow is used in that request

This is not a replacement for pagination, since it may still be needed and it could coexist with this flow

Acceptance criteria:

• [ ] Wearables are retrieved using streams and RPC calls
• [ ] WebInterface flow is functional
• [ ] We can chose which flow to use through a feature falg

[mikhail-dcl]

Closed because Renderer will be consuming Lambdas directly and no middleware is needed anymore