Feature Request: Support hierarchical CLAUDE.md inheritance

Current behavior:

• Only reads the closest CLAUDE.md file
• If src/membership/CLAUDE.md exists, ignores parent CLAUDE.md files

Requested behavior:

• Read both parent and child CLAUDE.md files
• Combine global settings (from parent) + domain-specific settings (from child)

Use case:

• Global coding conventions in root CLAUDE.md
• Domain-specific business logic in subdirectory CLAUDE.md
• Avoid duplication while maintaining hierarchy