F2P steel bar smelting fix

What's Changed

• Added a MEMBER_WORLD check to the code that makes cannonballs, so F2Pers see (when using a steel bar on a furnace) nothing interesting happens instead of you heat the steel bar.

How Has This Been Tested?

When using a steel bar on a furance:

• Tested in member's world, I am able to make the cannon ammo with the mould in my inventory.
• Tested in F2P world, I see nothing interesting happens.