[BUG] - PreferenceDataset

[patrickfleith]

Bug Description

When running a PreferenceDataset.generate()

Problem 1
Inconsistent expected number of rows printed vs logged.

Expected 78 preference pairs
2025-11-20 11:46:47 | INFO     | datafast.datasets:generate - Starting PreferenceDataset.generate() | Expected rows: 234

Problem 2
When a validation error is thrown during llm.generate() the PreferenceDataset generation loop is broken. We need to catch, log, and gracefully continue