Function init_prunable_finalized_blocks_archive 

async fn init_prunable_finalized_blocks_archive<TContext>(
    context: &TContext,
    partition_prefix: &str,
    page_cache: CacheRef,
) -> Result<Archive<TwoCap, TContext, Digest, Block>, Error>
where
    TContext: Clock + Metrics + Spawner + Storage + BufferPooler + Clone + Send + 'static,

Initialize the prunable archive that holds recently finalized blocks.

This archive only holds at most retention_blocks items at any time; older blocks are removed by the prune step in Hybrid.