npcUtil Trade functions do not account for future space available

[claywar]

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• [x] I have specified what branch this happens on branch: EDITME

Additional Information (Steps to reproduce/Expected behavior) :

If player inventory is full on trade, a failure will occur if an item is awarded on trade complete.

Example: Inventory Full, required trade is 5 items, onTrade complete awards one item.

Trade 5, and after trade there should be sufficient space to receive one, but failure is still returned.

[zach2good]

That's correct no? I can't trade my ambu currency/items when I have a full inventory, even if the end result should be one less space than I started with. (I think)

[claywar]

I don't recall it happening in retail, but definitely a good thing to confirm.

[TeoTwawki]

Retail exhibits the same behavior in all cases I have ever encountered - requiring space to exit prior to trade initiation disregarding space freed by the trade