[ot][spam][crazy] log: append-only random-access data

[Undiscussed Horrific Abuse, One Victim of Many]

            # find leaf count and leaf depths
            leaves = [*self.leaves()]
            max_depth = len(leaves).bit_length()
            current_entry = None
            for leaf_depth, leaf_offset, leaf_data in leaves:
                # leaves that have depth that is too deep can be added
to the index so as to find them quickly
                    # or a parent of them could be added

                # when we find a leaf that is too deep, we can start
an index entry
                # we can then continue moving on, and move the index
entry to its parent to include adjacent leaves.
                # if we reach prev_flush as the only shared parent,
then we write out the entry using the last too-deep item as the
endpoint
                # instead if we find another too deep item, we make it
the last, and continue on