feat: Add MatchAny positional args validator

[walle250ai]

Adds MatchAny(pargs ...PositionalArgs) as the OR-semantics complement to the existing MatchAll. Returns nil if any validator passes; if all fail, returns a combined error listing each individual failure. Zero validators passed returns nil (vacuously true, consistent with MatchAll behaviour).

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[marckhouzam]

Thanks. This seems reasonable

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[marckhouzam]

Ah, and the linter failed.