Add IVR/IVS tutorial notebooks #10

Status:

• IVS notebook — tested and working
• IVR notebook (ivr_style_rewrite_run.ipynb) — needs a retry loop added

The current IVR notebook uses a Best-of-N parallel strategy (fire N generations, pick the first that passes all requirements), but lacks an actual retry loop. If none of the N candidates pass on the first batch, it just picks the best-scoring one rather than retrying with a new batch.

TO DO

Add a proper IVR repair loop that:

• Retries generation up to LOOP_BUDGET times (already configured as 3)
• Only falls back to best-scoring if all retry rounds are exhausted