[1.20.1] Item duplication bug due to wrong priority for iron downgrade

[Windows2066]

Functional Storage Version: 1.20.1-1.2.12

Titanium Version: 3.8.32

In this bug, you can duplicate items esaily:

1. put a copper upgrade(or any other upgrades) and an iron downgrade in a drawer
2. put more than 64 items in the drawer
3. take the upgrade away, just leave a iron downgrade in the drawer
4. put another empty drawer beside it and put a item in it(same as the items in the drawer with iron downgrade)

5. put a puller upgrade in the drawer with iron downgrade and orient it to match the other drawer

then the items start to duplicate

[Windows2066]

This bug even allows the number of drawer items to break the limit

[TheAshenWolf]

I'd like to add here that the speed of the duplication depends purely on the amount of items above the 64 limit.
Additionally, this type of insertion into a barrel ignores the void upgrade.

This leads me to believe that "Remove" part of code is being called with a negative amount resulting in an unchecked addition.