Prevent wasting rune when adding bad property to item

[Anachorn]

Hi,
Runed items are sometimes very valuable and ruining them due some misunderstanding or misclick hurts,

It would be nice QoL change to prevent heartbreak if when trying to add using dweomencrafting to a runed item a property that already exists on it, it will either prevent you from doing so or just not waste the rune if no new property was added, so you will only lose the gold.

[Irongron]

Approved.