feat(skills): add wellarchitected.github.com content to iac-terraform-orchestration-ops

## Summary

Add references and patterns from https://wellarchitected.github.com to the `iac-terraform-orchestration-ops` skill.

## Rationale

The GitHub Well-Architected framework provides best practices for infrastructure operations, GitOps workflows, and CI/CD patterns that complement Terraform orchestration operations.

## Scope

- Add wellarchitected.github.com as a reference
- Incorporate framework patterns for GitOps and infrastructure automation
- Add guidance on operational workflows, approvals, and change management per the framework

## Related Skills

This is part of a broader effort to add wellarchitected.github.com content to:
- cicd-github-actions-dev
- cicd-github-actions-ops
- github-actions-dev
- github-app-dev
- iac-terraform-modules-eng
- iac-terraform-orchestration-ops (this issue)