Add new skill definitions organized by category:
Personal:
- conversation-summary: summarize AI conversations into Obsidian notes
- knowledge-gardener: vault-aware semantic search and Zettelkasten workflows
Productivity:
- grill-me: alias for running a grilling session
- grilling: relentless interview to stress-test plans
- handoff: compact conversation into handoff document for agent continuity
- writing-great-skills: reference guide for skill authoring best practices
- glossary: domain model for skill-building terminology
