1. Added item trading amount limit function per player.
2. Added 'resetTradingVolume' command.
3. Significantly improved execution speed of 'deleteOldUser' command.
4. Fixed an issue where maxStock and discount settings were lost when using the 'edit' command.
5. Fixed an issue where the discount setting value was lost when using the recommended value setting function.
6. Improvements related to max stock limit. Improvements to sell some quantities if available.
7. Fixed an issue where, in very exceptional scenarios, selling an item could cause the item to disappear and not be paid.
8. Fixed an issue where item delivery cost calculation would sometimes cause an exception.
9. Other minor fixes and improvements.