feat: add batch withdrawFees function for gas optimization

[sqhell]

• Implement batch withdrawFees(Token[], uint256[], address) function
• Add comprehensive unit and integration tests (12 new tests)
• Include detailed security analysis documentation
• Maintain full backward compatibility with existing withdrawFees
• Provide 30,000+ gas savings per additional token in batch

Implementation Details

• Added batch withdrawFees overload to ICarbonController interface
• Implemented function in CarbonController with proper validation
• Maintains same access control (ROLE_FEES_MANAGER required)
• Atomic operations with individual amount capping per token
• Comprehensive input validation and error handling

Testing Coverage

• 12/12 new batch withdrawal tests passing
• 9/9 existing fee withdrawal tests still passing
• End-to-end testing completed on Tenderly testnet
• Gas optimization verified through comparative analysis

Security Analysis

• Comprehensive security documentation included
• Access control mechanisms thoroughly analyzed
• Attack vector analysis with mitigation strategies
• Gas-based DoS protection evaluation
• Input sanitization and edge case validation

Gas Optimization

• Estimated 30,000-36,000 gas savings per additional token
• Reduces external call overhead for multi-token operations
• Maintains security while optimizing operational costs

Addresses: bancorprotocol#106