chore: block subscription, deactivate actors

[SantiagoPittella]

This PR:

• Removes the NtxBuilder proto api.
• Refactors the Ntx Builder to use a BlockSubscription instead of a mempool one.
• Temporary deactivates the actors.
• Streams the blocks until sync and marks is_synced to true when reached, after that it cointinues fetching and updating the local tip.

Caution

This change halts the execution of network transactions

[igamigo]

Would it make sense to build this on top of #2095 considering #2095 (review)?

[Mirko-von-Leipzig]

This lgtm, some minor comments. Ideally this would include the store -> rpc gRPC service change since the former may or may no longer exist when this merges.

[Mirko-von-Leipzig]

I think we can simplify the logic if we separate out the "bootstrapping" such that we always have at least the genesis block in the database. Similar to how the current store is bootstrapped.

But we can do that in a follow-up.

[Mirko-von-Leipzig]

#2130

[Mirko-von-Leipzig]

Would it make sense to build this on top of #2095 considering #2095 (review)?

I've actually come to the conclusion that merging this one first may resolve a lot of the questions people have by virtue of removing the network account stuff.

[Mirko-von-Leipzig]

@SantiagoPittella I've made the following changes to unblock and move other PRs along,

• Replace block-producer and store clients with RPC client (allows me to yank gRPC services)
• Since tx submission now goes via RPC
  • Validator is no longer required
  • Tx inputs must now be sent
  • RPC will require authentication to allow ntx Support network transaction submission in RPC #2131