History of checkpoint 2 changes

In crates/hub/src/tlog.rs, lines 773–778 on 93f445fa50d829625f9666e9f92b352e428b7105d5ce7944d3132902d7da49c8. 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 773,778:crates/hub/src/tlog.rs.