allow interface itemstack handler to accept over sized stacks

src/main/java/appeng/container/slot/OptionalSlotFake.java

@@ -62,6 +62,11 @@ public class OptionalSlotFake extends SlotFake implements IOptionalSlot {
         return this.host.isSlotEnabled(this.groupNum);
     }
 
+    @Override
+    public int getSlotStackLimit() {
+        return Integer.MAX_VALUE;
+    }
+
     @Override
     public boolean isRenderDisabled() {
         return this.renderDisabled;