Function rule_specificity 

pub fn rule_specificity(rule: &RecipeRule) -> usize

The matching rules’ styles merged in order (token refs kept). How specific a rule is: one point per when condition (a state list counts each state). VAPP-90: rules merge in SPECIFICITY order, like the CSS the web renderer compiles them to — a base rule (no when) never shadows a checked/focus/variant rule that sits before it, which is what a child theme’s appended base override used to do under plain source order. Ties keep source order (later wins). Mirrors ruleSpecificity in packages/exponential-ui/src/theme.ts.