🌟 Slot Expansion

Users can expand up to 8 slots. With this function, users can run with 8 watches installed at the same time. This function was created for the convenience of users, and the cost of slot expansion is indicated below. For example, if the slot is expanded 4 times, the total number of slots becomes 5, and 5 watches from 0M can be mined at the same time.

Slot Expansion	SWP Consume
Basic 1 -> 2	2000 SWP
2 -> 3	4000 SWP
3 -> 4	6000 SWP
4 -> 5	8000 SWP
5 -> 6	10000 SWP
6 -> 7	20000 SWP
7 -> 8	40000 SWP