docs(code): update AHP documentation with agent-monitors-agent architecture

- Add agent-monitors-agent architecture as recommended approach
- Remove deprecated LLM-powered harness sections
- Update code examples to use skill_dirs for AHP Server agent
- Fix MDX syntax errors (escaped quotes and newlines)
- Update both Chinese and English documentation
- AHP Server agent now mounts ahp_skills directory to use /detect-dangerous-operation skill
- Clean up obsolete test files and examples

Author: RoyLin