ADC crashes when saving empty crop

[rhine3]

Sometimes a detection's bbox boundaries are so small that they round to a set of bbox boundaries with zero area (e.g., [400, 0, 500, 0]). When this happens, ADC crashes with the response ValueError: cannot write empty image as JPEG. This line is included in the traceback:

ami-data-companion/trapdata/db/models/detections.py

Lines 379 to 382 in a33746a

	detection.save_cropped_image_data(
	source_image=image,
	base_path=user_data_path,
	)

If we just validate that bbox_area is a positive value before trying to save it, we could skip saving when the bbox is empty. I replaced those lines above with this temporary patch on my own machine:

                if area_pixels is not None and area_pixels > 0:
                    detection.save_cropped_image_data(
                        source_image=image,
                        base_path=user_data_path,
                    )
                else:
                    logger.warning(
                        f"Detected object with bbox {detection.bbox} has area 0, skipping cropped image save."
                    )

However, I don't know how this will affect downstream operations like trying to display an expected cropped image that is not there.