History of checkpoint 1 change

In crates/hub/src/flow.rs, lines 1455–1471 on 1c52d940b4a0435d9a46400293c69d8b6588231b3f3b1fafd7ead56feb7c1d3a. 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 1455,1471:crates/hub/src/flow.rs.