Only tested on 1.18.1 and 1.17.1
It is expected to work normally in versions below 1.17.
Please let me know if there are any problems.

- Fixed interval related bugs of stabilizing and fluctuation.(Does not work if set longer than 24 in-game hours)
- Fixed an issue where incorrect values were applied when dividing or multiplying prices with the editAll command
- Added one more pair of price change arrow strings.
(to set purchase and sale separately)
- Code refactoring. Slightly improved performance.