History of checkpointer 2 changes

In crates/hub/src/tlog.rs, lines 748–765 on 5f3fa151688e8b1d91d5cd3dfe316416683c13a6d1244fc1ea4859dce74b4e99. 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.