Stormlight Fractal Sword and Armor

Added a new way to obtain Fractal equipment:
- Structure chests now have a 33% chance to contain one random Fractal sword or armor piece.
- Village chests are excluded.
- Each item includes its base enchantments and one compatible random level X enchantment, excluding curses.
- Fractary Zombies still drop their sword and complete armor set.
- The existing 15% chance per valid natural spawn attempt remains unchanged.
- Existing equipment stats, powers, and textures are preserved.