Parquet filter pushdown causes query slowdowns for specific query patterns

Enabling datafusion.execution.parquet.pushdown_filters causes specific ClickBench queries to slow down by 1.06x to 3.28x. Affected queries include Q2 (1.14x slower), Q6 (3.28x slower), Q10 (1.34x slower), Q11 (1.26x slower), Q12 (1.19x slower), Q14 (1.16x slower), Q19 (1.22x slower), Q24 (1.37x slower), Q25 (1.33x slower), Q26 (1.55x slower), Q40 (1.40x slower), Q41 (1.29x slower).

Profile affected queries using the documented benchmarking procedure. Run queries with and without pushdown_filters setting. Compare datafusion.parquet.pushdown_eval_time and datafusion.parquet.pushdown_rows_filtered metrics. Investigate whether dynamic filters (aggregate or join) are being pushed down inappropriately. Consider implementing selectivity-based skip logic for low-selectivity filters.