History of checkpointer 2 changes

In crates/hub/src/tlog.rs, lines 748–765 on a3ba7cc106738520cd2c50e68b9b31b1bcf006364c25c875770cc3541c6732bf. Every change that wrote or deleted one of these lines, or deleted a line from between them. Exact, because each line keeps its identity across edits; edits elsewhere in the file are not here. Also: oxy log -L 748,765:crates/hub/src/tlog.rs.