Add multi-framework dataset setup for RF-DETR, YOLOX, and YOLOv6

- Create dataset_coco/ for RF-DETR (COCO format)
- Rename dataset_split/ to dataset_yolo/ for clarity
- Add setup_datasets.py script for automated multi-format setup
- Update YOLOv6 script with correct 10-class configuration
- Update README with framework comparison and training instructions
- Update .gitignore to exclude both dataset directories

train_yolov6.py

@@ -68,8 +68,8 @@ def train_yolov6(
         f.write(f"""train: {train_dir.absolute()}
 val: {valid_dir.absolute()}
 
-nc: 1
-names: ['knot']
+nc: 10
+names: ['Live knot', 'Dead knot', 'Knot with crack', 'Crack', 'Resin', 'Marrow', 'Quartzity', 'Knot missing', 'Blue stain', 'Overgrown']
 """)
     
     print(f"\n{'='*60}")