More optimizations and fixes

• Reduced the memory usage for stunning/breaching/leeching reforges
• Buffed Stunning reforge duration, from 1s -> 2s.
• removed unnecessary @a in certain situations
• Added Storage for Player data (id & level) & Reforge Anvil (id). They will be saved on creation/update, and load on reload.
• Added small description for how to gain forging xp, on lvl 0.
• Changed unnecessary @e[...] for custom mobs and moved to somewhere else.