Vector runtime: containment expression (`in` operator) returns empty results

[mattnibs]

Summary

The in containment operator returns empty results in the vector runtime when searching for complex values recursively. The SAM runtime correctly finds matching records, but the vector runtime produces no output.

Reproduction

echo '{s:"foo"} {s:"foo",t:"bar"} {a:{s:"foo"}} [1,{s:"foo"},2]' | super -z -c 'where {s:"foo"} in this' -

Expected:

{s:"foo"}
{a:{s:"foo"}}
[1,{s:"foo"},2]

Actual (vector): Empty output (no records returned)

Test reference

book/src/super-sql/expressions/containment.md:67

Discovered via make test-heavy which runs documentation examples through the vector runtime.