History of plan 2 changes

In crates/hub/src/diffusion.rs, lines 659–679 on 47932fa8d6f3541455824fbc071a49fd91d71e887d4a9f911081c30e5d8c00b2. 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.