precursors from proteins validated with at least 2 peptides

--- Resubmitted on 2026-03-30 16:11:17 UTC ---
Changes detected:
  Row count: 58045 → 61566
  Added columns: ['epsilon_precision_mean', 'epsilon_precision_median', 'log2_empirical_mean', 'log2_empirical_median']
  Removed columns: ['logIntensityMean']