grafana: fix DuckDB datasource and deploy github intelligence dashboard
- remove readOnly:true from analytics volume mount — DuckDB needs
filesystem write access for lock files even in read mode
- update github-intelligence dashboard table panel to query
github_action_items (dbt-scored) instead of raw inline formula
- deploy dashboard via just dashboards
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>