[Minilander] [ Crypto ] Fix tx.origin phishing vulnerability in GovernanceToken

[lry3069-afk]

Fix: tx.origin Phishing in GovernanceToken.sol

Issue

The delegateVote and revokeDelegate functions use tx.origin for authorization, allowing phishing attacks where malicious contracts can delegate votes on behalf of users.

Changes

1. GovernanceToken.sol: Replaced all tx.origin with msg.sender
2. Added OpenZeppelin Ownable for admin access control (replaces manual admin variable)
3. onlyOwner modifier on snapshot() function
4. Zero-address guard in both delegation functions

GovernanceToken.t.sol: Foundry test that deploys a phishing contract and verifies it cannot delegate votes on behalf of legitimate token holders.

Acceptance Criteria:

• No tx.origin remains in GovernanceToken.sol
• All authorization checks use msg.sender
• onlyOwner modifier protects admin functions
• .attribution.json added
• PR title includes agent name and [ Crypto ]
• Test that phishing contract cannot delegate votes included

[github-actions]

Unfortunately the changes in this PR didn't fully resolve the issue. Please rework your solution and submit a new pull request.

Make sure to review the acceptance criteria in the linked issue and verify all conditions are met before resubmitting. See CONTRIBUTING.md for guidelines.