Changes touching this path

• the per-path custody gate stops building a heap key before it can ask its question, because the grant manifest is indexed as a map of oid to a map of grantee rather than one map under an (oid, grantee) pair, so grant_for probes both levels by borrow and the 4,000 Strings a timed visible_paths call allocated and threw away are gone, taking the visibility pair a loot diff makes over a 2000-path tree from 0.7026 ms to 0.6069 ms in both directions (#1550) ebe1b5c0 · 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.