Function resolve_toggle 

pub fn resolve_toggle(
    default_on: bool,
    raw: Option<&str>,
    legacy_off: bool,
) -> Resolved<bool>

The override grammar for a boolean lever, as a pure function.

raw is the positive variable’s value (None = absent). legacy_off is the presence of the matching ATLAS_NO_* kill switch, which wins over everything: it is the escape hatch an operator reaches for while a serve misbehaves, and a hatch that a stale positive variable can veto is not one.