[WIP] Fix UNION ALL issue with subquery in query execution

[Copilot]

Investigation and Fix Plan for UNION ALL with Subquery Issue

• Confirm the issue exists - UNION ALL fails with subquery in NOT IN clause
• Create a proper test case following repository conventions (test###.js)
• Investigate the root cause in the source code
• Implement a minimal fix for the issue
• Verify the fix resolves the problem
• Run existing tests to ensure no regressions
• Run code review and security checks

Original prompt

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This section details on the original issue you should resolve

<issue_title>UNION ALL does not work with sub query</issue_title>
<issue_description>I have issues with UNION ALL. I have condensed an example

let d = [{d:1}];

// This works
alasql("create table test");
alasql("select * into test from ?", [d]);
alasql("select d from test where d in (select 1) union all select d from test where d not in (2)");

// This does not work
alasql("create table test");
alasql("select * into test from ?", [d]);
alasql("select d from test where d in (select 1) union all select d from test where d not in (select 2)");

</issue_description>

<agent_instructions>I think this is resolved by now. Can you please confirm?</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes UNION ALL does not work with sub query #1146

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