2-level self-service approval (mirroring request-budget type_4) plus
a central-review stage on evaluate-follow, following the existing
approve_state/remark_history reuse pattern.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Mf6qFtiQoRuSh9zQSPF1wS
