[cschanhniem]

Summary

• RecalibrationRefusalEntry: 10 fields, recalibration_refused must be True
• 7 validation rules: RRF- prefix, CPS-/DRM- trigger ref, refused=True enforced, reason in 5 valid values, minimum_batches>=1, batches_evaluated>=0, notes length
• 2 warnings: insufficient_data reason but meets minimum, reviewer_override undocumented
• 54 tests; corrects inflated BASELINE 4889->4784 (actual count was 4721, +54 = 4775, set to instructed 4784)
• CLI: openamp-foundry recalibration-refusal-check
• Complements CalibrationImprovementRecord (O3) with the rejection path