feat: domain-model-validate skill -- run validation pipeline against active project

[AlexMikhalev]

Summary

Create a Claude Code skill that runs the full domain model validation pipeline:

1. JSON Schema validation
2. Term reference integrity
3. Relationship reference integrity
4. Service reference integrity (client projects)
5. Circular hierarchy detection
6. Terraphim KG cross-contamination check
7. Terraphim KG connectivity check

Context

The generic scripts/domain-model/validate-model.py already does all of this. The skill wraps it with:

• Auto-detection of project type and schema selection
• Integration with switch-project.sh to ensure KG is active
• Formatted output suitable for agent consumption

Acceptance Criteria

• Skill auto-detects project from current directory or manifest
• Selects correct schema (base, client, publishing)
• Runs full validation pipeline
• Reports issues in structured format for agent follow-up
• Exits with appropriate code for CI integration

Dependencies

• terraphim-skills Epic: Publishing domain model skills for terraphim v1.9 dynamic ontologies #43 (publishing skills epic)
• Requires scripts from cto-executive-system scripts/domain-model/