History of tiers 3 changes

In crates/flow/src/runner.rs, lines 302–321 on 8f211e20bea5e995d04f82b9aab8961aea9b729aafe87a2894cadba90cd0c722. 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 302,321:crates/flow/src/runner.rs.