History of Sky::step 2 changes

In crates/backdrop/src/sky.rs, lines 428–483 on 5d818ec7d5fcbc9f08a9210d00cb0197705cd79eeeaf35507232317f440c6d27. 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 428,483:crates/backdrop/src/sky.rs.