Add formatExplainJSON exporter for ClickHouse EXPLAIN AST json = 1 with vendored reference suite#26

Copilot wants to merge 2 commits into

mainClickHouse/clickhouse-js-parser:mainfrom

copilot/check-ast-format-synchronizationClickHouse/clickhouse-js-parser:copilot/check-ast-format-synchronizationCopy head branch name to clipboard