Changes touching this path

• lane gc takes the tree down marker-last so a reap that fails on a held file leaves the lane identifiable and reapable on retry, a held file is named as one with the re-run advice, and an emptied shell that will not go is re-stamped with its id (#1275) c1f6a485 · dbf3dbe6…

Renames are not followed. loot's tree maps a path to an address, so a rename is a delete and an add. This list is the history of the name, not of the bytes.