feat: add L1 processed value

[frisitano]

Overview

This PR introduces a new L1 notification variant that notifies the orchestrator of the L1 block number that has been processed up to:

    /// A notification that the L1 watcher has processed up to a given block number.
    Processed(u64),

This value is persisted in the database and served in the rollupNode_status rpc method.

[codspeed-hq]

CodSpeed Performance Report

Merging #356 will not alter performance

_{Comparing feat/add-l1-processed-block (f60eeef) with main (5472bfd)}

Summary

✅ 2 untouched

[greged93]

lgtm!