[draft] API split and deduplication

[liran-funaro]

Type of change

• Improvement (improvement to code, performance, etc)
• Breaking change

Description

• Conform to the Google protobuf naming conventions. E.g. emptypb.Empy, durationpb.Duration
• Split the API into two main components:
  1. committerpb: all the API that are used to publicly access the committer. It will eventually be moved to the common repository.
  2. servicepb: all the internal API
• Deduplicate messages and remove unused RPC

Alternatives

• committerpb can be split into applicationpb and committerpb, where the former will include the block_tx.proto and config.proto.

Related issues

• address [proto] Unnecessery protobuf messages #111
• address [API] separating external and internal API #44
• address [proto] Unused RPC in the Coordinator: GetLastCommittedBlockNumber #48