The goal of this milestone is to polish pipeline for better efficiency while extracting from websites:

1. Allow user to change configuration (LLM model, prompts, concurrency limits, API key, field constraints) from web interface
2. Fix properties export
3. Fix hotkeys (remove "sticky key" effect)
4. Make product sieving more forgiving, allowing parser to add products, which are out-of-stock
5. Option to reprocess selected products in case of LLM errors
6. General stability and UX updates for frontend
7. Update parser to force user to re-select XPATHs when re-visiting the site