Add test: mergeConditionNodes(HAVING, QUALIFY) correctness untested — existing test uses identical conditions

[clickgapai]

Found via ClickGap automated review. Please close or comment if this is incorrect or needs adjustment.

Retrospective finding from a historical scan of PR #62619 (merged 2024-04-23). Confirmed on current codebase — close with a note if already fixed.

This is a test-only PR — no source code changes. Please review: test quality, whether the claimed coverage gaps are real, and whether test output makes sense.

Adds test coverage for 1 untested code path(s), found during automated review of PR #62619.
That PR PR adds support for the QUALIFY SQL clause to the new analyzer + planner. Changes cover: (1) parser — new QUALIFY keyword in CommonParsers.h, ParserSelectQuery parsing branch, and ParserAlias::restricted_keywords; (2) AST — new Expression::QUALIFY enum + accessors in ASTSelectQuery, `f

1. mergeConditionNodes(HAVING, QUALIFY) correctness untested — existing test uses identical conditions
src/Planner/Planner.cpp:1978
Risk: Planner.cpp:1975-1982 enters the no-window QUALIFY fallback. When both HAVING and QUALIFY are present (line 1977), it calls mergeConditionNodes({getHaving(), getQualify()}, ...) (line 1978) whic
What's unique vs PR tests: PR test 03095_window_functions_qualify.sql line 15 uses HAVING key = 0 QUALIFY key == 0 — IDENTICAL conditions on both sides, so the merge result is invariant to dropping one operand or swapping AND
Try it on ClickHouse Fiddle

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