Setup crop

[jwboth]

This pull request refactors and improves the crop correction workflow in the application, making the handling of crop corners more robust and user-friendly. The main changes include switching from an ordered list of crop points to named corners throughout the codebase, updating configuration formats, and enhancing the GUI to support interactive crop correction. Additionally, the configuration loading and saving logic is improved for better reliability.

Core logic and configuration changes:

• The crop assistant (crop_assistant.py) now classifies selected points into named corners (top_left, bottom_left, bottom_right, top_right), making the crop process robust to the order in which points are selected. The configuration output now uses these named corners instead of an ordered list. [1] [2] [3] [4] [5] [6] [7]
• The configuration files (config.json, config_co2.json) and the configuration loader (curvature.py) are updated to use named corners for the crop region. The loader reconstructs the legacy pts_src as needed for backward compatibility. [1] [2] [3] [4]
• The deprecated crop method in the curvature correction class is removed, as the new approach supersedes it.

GUI and workflow enhancements:

• The GUI now includes an interactive "Crop correction" step in the setup sidebar, with contextual help and support for running the crop assistant. [1] [2] [3]
• The setup workflow and process runner are updated to support the crop correction step, ensuring that configuration changes are saved and reloaded appropriately when running subprocesses. [1] [2] [3] [4] [5] [6]

Bug fixes and minor improvements:

• Typo fixes in docstrings and improved error/warning messages for configuration loading. [1] [2] [3]

These changes make crop correction more reliable, improve user experience, and ensure the configuration format is consistent and future-proof.