refactor(agent): factor CLAUDE.md from 213→56 lines with prompts submodule

[CodeMonkeyCybersecurity]

Summary

Apply RFC-001 progressive disclosure architecture to Helen's CLAUDE.md.

Problem: CLAUDE.md accumulates ad-hoc content that loads on every agent session, consuming tokens with content irrelevant to the current task.

Solution: Replace with 56-line thin proxy that:

• Keeps essential commands and project identity
• References upstream governance contracts via @third_party/prompts/ @imports
• Loads remaining detail only when needed

Changes

• Replace CLAUDE.md (213 lines) with thin proxy (56 lines)
• Add third_party/prompts submodule (cybermonkey/prompts governance-as-code)

References

• RFC-001: Progressive Disclosure Architecture (cybermonkey/prompts)
• Parallel: hecate #2374, hera ci(deps): bump fossa-contrib/fossa-action from 2 to 3 #7