History of checkpointer 2 changes

In crates/hub/src/tlog.rs, lines 597–614 on bb018142cca7d18bd4f910c992653e74af783e8d2c7e80a98f9e5685553a7c63. 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 597,614:crates/hub/src/tlog.rs.