julia

334c3167 - subtype: save some union stack space for ∃ free cases. (#58159)

subtype: save some union stack space for ∃ free cases. (#58159) and avoid eager UnionAll unwrapping to hit more fast path. close #58129 (test passed locally) close #56350 (MWE returns `Tuple{Any, Any, Vararg}` now.)