[Feature] Require human Git authors

[JunchenMeteor]

Summary

Prevent automated releases and coding agents from using bot or AI identities as Git authors or committers.

Expected Behavior

All new commits use an approved human identity: Connor, ConnorQi, or JunchenMeteor.

Proposed Changes

• Add the author and committer rule to AGENTS.md.
• Configure Release Manager commits as JunchenMeteor <15767428+JunchenMeteor@users.noreply.github.com>.
• Leave existing Git history unchanged.

Test Plan

• Validate scripts/release-manager.mjs syntax.
• Confirm the release manager no longer configures github-actions[bot].
• Confirm the resulting commit uses an approved human identity.

[JunchenMeteor]

Implemented and merged in #149.