Function list_to_large_binary_expr 

pub fn list_to_large_binary_expr(expr: Expr) -> Expr

Wrap a List<T> or LargeList<T> expression as a LargeBinary CypherValue.

Arrow cannot cast List<T> → LargeBinary natively, so we route through the _cypher_list_to_cv UDF. Used by coerce_branch_to when CASE branches have mixed LargeList<T> and LargeBinary types.