feat: unified config.yaml with extensible model presets (A-D data-driven, E/F ready)

- config.yaml canonical for stream/models/counting/batch/output/camera
- models.modes hold engines+class filters only; conf/iou/min_bbox in detection_params
- predict.py derives tracker roles structurally (no per-mode branching)
- dashboard mode switch validates + persists atomically to config.yaml
- .env keeps secrets/deployment only; zones.json geometry; tracker.yaml hyperparams
- batch_mode.json keeps manual/auto batch mode; legacy model_mode ignored w/ warning
- src/detection+tracking gain iou param (default 0.7 = no behavior change)

deploy_to_jetson.py

@@ -17,6 +17,7 @@ files_to_sync = [
     ("templates/base.html", "/home/jetson/karung/templates/base.html"),
     ("counter_dashboard.py", "/home/jetson/karung/counter_dashboard.py"),
     ("predict.py", "/home/jetson/karung/predict.py"),
+    ("config.yaml", "/home/jetson/karung/config.yaml"),
     (".env", "/home/jetson/karung/.env"),
 ] + [
     (f"models/{f}", f"/home/jetson/karung/models/{f}") for f in MODEL_ENGINES