History of plan 2 changes

In crates/hub/src/diffusion.rs, lines 659–679 on a22e4aec2e28e7e116863dacacb175a7b7e495581073e1b757840b5ae33ec0b5. 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 659,679:crates/hub/src/diffusion.rs.