pub fn steps_from_yaml(yaml: &str) -> Result<Vec<Step>, String>Expand description
Parse the canonical on-disk dayscript form back into steps — the inverse of steps_to_yaml.
This MIRRORS day-cli’s parse_flow (crates/day-cli/src/script.rs) on purpose: it accepts the
same - <op>: {…} entries, the - screenshot: name / - pause: 1.5 scalar shorthands, and a
bare - nav_back: (null params). The two are kept in step by a test that round-trips the CLI’s
own smoke.yaml template through here. (day-cli does NOT call this — the CLI deliberately does
not depend on day-script’s runtime graph — so the shared shape is guarded by test, not code.)