Support string coercion for array-form type in OpenAPI 3.1 (runtime)

[modosc]

i started trying to wire up the recent 3.1 changes into committee and ran into an issue which this tries to resolve.

problem

committee passes query, path, and form params to openapi_parser as raw Strings and relies on coerce_value to convert them. 3.1 removed nullable, so a nullable param is written as type: [integer, "null"]. array-form type picks a type by matching the value's class, so "5" matches nothing and fails validation. every request that sends a nullable non-string param is rejected.

solution

• with coerce_value on, a String that matches no type in an array-form type is coerced by trying each listed non-null type in order ("5" against [integer, "null"] becomes 5)
• returns the first type that validates, otherwise the first type's error
• exact class matches are unchanged (a String against [integer, string] stays a String)
• not gated on document version, matching the other 3.1 runtime changes; array-form type is already flagged in 3.0 docs by TypeArrayIn30
• no new SpecValidator rule, since this only changes runtime behavior for an existing keyword

depends on #211 (this branch includes its commit; only the last commit is new).

[geemus]

lgtm, thanks!