Update Solidity Version and Refactor Contracts to Remove SafeMath Redundancy

[floor-licker]

This PR provides improvements to the Solidity codebase by updating to v0.8.0 and refactoring the contracts to remove the dependency on SafeMath.

• Upgrade to Solidity v0.8.0
  Solidity 0.8 introduces built-in overflow and underflow checks, which eliminate the need for external libraries like SafeMath. Solidity 0.8 also introduces gas optimizations for arithmetic operations, so this update not only streamlines contract execution but could also lower gas costs for end users. Solidity 0.8’s built-in overflow/underflow checks are also more robust and efficient compared to the SafeMath library, which reduces the attack surface of the smart contracts.

• SafeMath Removal
  In updating to Solidity v0.8.0, the built-in safety features make the dependency on the safeMath library redundant. In doing this we remove the dependency on this external library and improve code readability.

This change improves security, maintainability, and gas efficiency. I believe this update is an important step toward keeping up to date with modern best practices in the ETH development community.

I appreciate feedback and am happy to assist with any further improvements or testing required. Please don’t hesitate to reach out.

My Telegram and X accounts are both linked in my bio.

[floor-licker]

@GianfrancoBazzani I was just wondering if you'd be able to take a look at this PR. Thanks!