Create:Fluid Stuffs [NeoForge]

Fix Multi Fluid Tank edge cases and capacity sync:

• Prevent crash when inserting a 9th fluid type (no available slot now safely returns 0 in fill).
• Correct Jade capacity display by reporting shared capacity without multiplying by tank count.
• Fix split behavior so detached single tanks reset to 1-block capacity instead of keeping merged capacity (e.g., 32B).