Add 19 behave scenarios covering uncovered paths in skill_service.py
and cli/commands/skill.py to bring coverage above the 97% threshold:
- show with includes, MCP servers, agent_skills, inline tools, Referenced By
- tools with mixed MCP/inline sources
- list with non-local namespaces
- remove without --yes (abort path)
- update with dependent skills (Affected Actors panel)
- service edge cases: skill_count, empty names, source filtering, no config_path
- add with missing-description YAML (validation failure)