Small refactor to s2025_perception_merge_Tianyu

[LucasEby]

I needed to move the cone_detection.py helper functions into their own utility file (perception_utils.py) so the sensor fusion sub group can use them easier. I additionally threw in some small refactors that should hopefully make the cone_detection.py file easier to work with:

• Added some comments to explain complicated sections of the cone_detection.py code
• Moved the file saving functionality in cone_detection.py to it's own function to reduce the size of the update function

I tested that the code performed the same way after the changes with the following commands:
roscore
rosbag play -l multiple_slanted_w_obstacle.bag
python3 main.py --variant=detector_only launch/cone_detection.yaml

[sonarqubecloud]

Quality Gate failed

Failed conditions
62.4% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud