Initial release of the api-credentials-hygiene skill:

• Audits and hardens API credential management covering environment variables, separation, rotation planning, and least-privilege principles.
• Provides credential mapping, rotation runbooks, least-privilege checklists, and optional .env templates with placeholders.
• Designed for integration and deployment scenarios to improve secret handling and auditability.
• Outputs technical documentation only; does not handle actual secrets or offer legal/compliance advice.
• Promotes secure workflows by preventing embedded secrets, minimizing permissions, and documenting access and rotation procedures.