Implement fuzz testing for Vertix contracts

[am-miracle]

Description:

To improve the security and reliability of the VertixNFT, VertixMarketplace, VertixEscrow, and VertixGovernance contracts, implement fuzz testing to identify edge cases, vulnerabilities, and unexpected behaviors. Fuzz testing will involve providing random or malformed inputs to critical functions (e.g., minting, listing, buying, dispute resolution) to ensure the contracts handle invalid or extreme inputs gracefully. This is critical for a decentralized marketplace handling valuable NFTs and non-NFT assets, as it reduces the risk of exploits and enhances user trust.