Improve self-repair summaries download

[ghost]

Is your feature request related to a problem?

In development environment this case is really present, but since you are adding some network latency around 150-200ms, the time to get the beacon summaries for all subset for a given date, become really long as minutes.

Hence we should propose a way to optimize the requests to reduce the latency

Describe the solution you'd like

The self-repair could be optimized in few ways:

Batch of the beacon summaries

For now, for each subset, we are doing multi requests to the same node, leading to latency (nb subsets(=256) * latency).

We should aggregate trough the election to know which nodes are responsible for which subset and then aggregate through aGetBeaconSummaries message

Stream responses

Because of the aggregation of summaries, network latencies and timeouts can occurred if the number of summaries and the transaction summaries inside are significant, as it's a single P2P call.

So we can stream transaction summaries like we are streaming transaction in the GetTransactionChain request, by doing multiple calls

Additional context

No response

[internet-zero]

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