Add operator YOLO label QA contact sheets

scripts/README.md

@@ -420,6 +420,25 @@ median box area, small-box share and sample-specific quality warnings. Treat
 next action is usually more positive AOIs, better validation coverage or more
 unique hard negatives rather than simply extending epochs.
 
+Render visual label QA contact sheets before spending CPU on another training
+run:
+
+```bash
+docker exec -it geointel python3 /app/scripts/render_operator_yolo_label_qa_contact_sheets.py \
+  --summary-path /app/storage/operator-data/yolo-building-aoi1024-cleanpx12vis035/yolo_tile_dataset_summary.json \
+  --output-dir /app/artifacts/operator-yolo-label-qa/aoi1024-cleanpx12vis035 \
+  --max-tiles 32 \
+  --columns 4 \
+  --thumb-size 256
+```
+
+The renderer writes `operator_yolo_label_qa_summary.json`,
+`operator_yolo_label_qa_contact_sheet.md` and `contact_sheet_001.png`. It draws
+existing YOLO labels on existing tile images only; it does not run inference,
+train a model, fetch providers or create fake detections. Missing image files,
+missing label files and invalid YOLO rows are reported in the JSON/Markdown
+artifacts.
+
 Current Tower audit status:
 
 - `yolo-building-tile-expanded160`: clean baseline; no missing/invalid labels.