Map of all the IPLD blocks that were included with this delegation DAG.
Usually this would be blocks corresponding to proofs, however it may
also contain other blocks e.g. things that capabilities or facts may
link.
It is not guaranteed to include all the blocks of this DAG, as it represents
a partial DAG of the delegation desired for transporting.
Also note that map may contain blocks that are not part of this
delegation DAG. That is because Delegation is usually constructed as
view / selection over the CAR which may contain bunch of other blocks.
A materialized view of a UCAN delegation, which can be encoded into a UCAN token and used as proof for an invocation or further delegations.