Add findByPersonIdIsNullOrderByCreatedAtDesc + findByPersonIdOrderByCreatedAtDesc to
OcrTrainingRunRepository. Add dto/TrainingHistoryResponse. Expose
GET /api/ocr/training-info/global and GET /api/ocr/training-info/{personId} on
OcrController, both requiring ADMIN; getSenderTrainingHistory guards person existence
via PersonService and returns 404 for unknown personId.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>