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Add max_parser_backtracks setting to limit query parsing complexity

Add a new setting max_parser_backtracks which allows to limit the complexity of query parsing. #61502 (Alexey Milovidov).
Introduces a new setting max_parser_backtracks to limit the complexity of query parsing in ClickHouse.

Why it matters

This setting is added to control and restrict the number of parser backtracks, preventing excessive resource consumption and improving query parsing reliability by limiting potential parsing complexity.

How to use it

Users can enable or adjust this feature by setting the max_parser_backtracks parameter in their ClickHouse server configuration or query settings to define the maximum allowed backtracks during query parsing.