New module (not package) that discovers .md files with YAML frontmatter
in the skills/ directory. Provides:
- SkillDef dataclass: name, description, content, tools, agents, file_path
- SkillRegistry: discovers skills, filters by agent, builds prompt sections
- _parse_frontmatter(): splits YAML frontmatter from markdown body
- get_prompt_section(agent_name): builds system prompt injection
- get_body(name): returns skill content without frontmatter
Files without frontmatter (data files) are automatically skipped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>