Function init 

pub(crate) async fn init<TContext>(
    context: TContext,
    page_cache: CacheRef,
    execution_node: Arc<TempoFullNode>,
    config: Config,
) -> Result<Initialized<TContext>>
where
    TContext: Clock + Metrics + Spawner + Storage + BufferPooler + Rng + CryptoRng + Clone + Send + 'static,

Initialize the marshal actor and its backing finalized-blocks store (the finalizations-by-height archive plus the Hybrid finalized blocks store), and advance marshal’s sync floor to max(marshal_stored_height, reth_finalized_height).

Both the consensus and follow engines must initialize marshal in exactly the same way so that nodes can switch modes without data migration. Use this function to maintain that invariant; differences between the two engines belong in Config.