History of plan 2 changes

In crates/hub/src/diffusion.rs, lines 659–679 on 76f93eaefe451cb3fe2daefccf8fd5b8c3bbb071a030a6876459bcde7ac54664. 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.