Harden zero-amount transfers; deprecate disputeInitiator; add compact config telemetry

[MontrealAI]

Motivation

• Prevent ERC20 edge-case reverts by avoiding zero-amount transfer and transferFrom calls in payout/bond paths.
• Ensure dispute initiator state is not misleading while preserving storage layout and mainnet bytecode budget.
• Improve operational telemetry for critical config setters with minimal, bytecode-conscious logging.

Description

• Added zero-amount guards for outbound transfers and introduced a small helper _tFrom to centralize safeTransferFromExact usage and skip 0-amount calls, and changed _t to skip 0 transfers in contracts/AGIJobManager.sol.
• Hardened bond intake flows so agent and validator bond paths do not call token transferFrom with amount == 0 (uses _tFrom and preserves locked*Bonds accounting).
• Marked Job.disputeInitiator as deprecated in-place (kept storage layout) and removed active setting/clearing to avoid misleading non-zero values while keeping the slot reserved.
• Added a compact ConfigUpdated(bytes32,bytes32) telemetry event (emitted via a tiny assembly log helper) for a small set of numeric setters (setPremiumReputationThreshold, setMaxJobPayout, setJobDurationLimit) to improve ops visibility while preserving bytecode headroom.
• Confirmed delistJob already uses nonReentrant so no change was needed there, and left ENSJobPages unchanged because it already emits owner setter events.

Testing

• Ran npm run build which compiled the contracts successfully with solc (no config changes to truffle-config.js and solcViaIR=false).
• Ran the repo bytecode guard (npm run size) and the AGIJobManager runtime bytecode is within the guard (artifact reports 24575 bytes), so size gating passes.
• No new unit tests were added to keep the diff minimal; compilation and bytecode-size checks succeeded.

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Codex Task