Harden token transfers and dispute-initiator lifecycle

[MontrealAI]

Motivation

• Avoid ERC20 corner cases where transfer/transferFrom calls with amount 0 revert on some tokens, and ensure dispute state is not left misleadingly set after settlement while preserving storage layout and public interfaces.
• Keep telemetry/ops visibility and bytecode within the existing EIP-170 guard without refactoring unrelated logic.

Description

• Add a zero-amount short-circuit in the internal helper function _t(address to, uint256 amount) so that outbound transfers never call token transfer with 0 (safe-guarding token compatibility).
• Prevent a safeTransferFromExact(..., 0) in the agent bond intake by making the agent bond transferFrom conditional while still accounting for lockedAgentBonds and storing job.agentBondAmount unchanged.
• Ensure dispute initiator hygiene by setting job.disputeInitiator = msg.sender when a dispute bond is posted and clearing job.disputeInitiator when the dispute bond is settled in _settleDisputeBond, keeping dispute lifecycle state consistent without changing storage layout.
• Minor housekeeping: removed the unused DeprecatedParameter error and make setAdditionalAgentPayoutPercentage revert with InvalidParameters, and rely on the hardened TransferUtils helper for skipping zero-value reward-pool contributions to keep diffs minimal and conserve bytecode.

Testing

• Ran npx truffle compile and compilation completed successfully.
• Ran the repository bytecode guard node scripts/check-bytecode-size.js and the AGIJobManager runtime bytecode was 24569 bytes which is within the 24575-byte EIP-170 safety margin.

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Codex Task