Add CI/CD documentation

[Suraj-kumar00]

Add CI/CD Documentation

Goal:
Add complete, beginner to advanced technical documentation for CI/CD to the DevOps learning website built with Fumadocs

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✅ Requirements:

• Document core CI/CD concepts and principles with diagrams
• Include popular CI/CD tools:
  • GitHub Actions
  • Jenkins
  • GitLab CI/CD
• Provide pipeline creation examples and best practices
• Configuration as code examples
• Integration with testing frameworks
• Deployment strategies (blue-green, canary, etc.)
• Security considerations in CI/CD pipelines
• External resources: blogs, tutorials, and video content

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Suggested Extras:

• Real-world CI/CD pipeline examples
• Comparison of different CI/CD tools
• Troubleshooting common pipeline issues
• CI/CD metrics and monitoring
• Cost optimization strategies for CI/CD pipelines

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Resource References:

• GitHub Actions: docs.github.com/en/actions
• Jenkins: jenkins.io/doc
• GitLab CI/CD: docs.gitlab.com/ee/ci
• YouTube: TechWorld with Nana and any good channel.