Docs: Add GitLab CI/CD + Strapi Integration Guide

closes #67 (closed)

📌 Description

This MR adds a comprehensive documentation guide for integrating Strapi with GitLab CI/CD.

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✅ Changes Included

• Added CI/CD pipeline explanation (build, test, deploy)
• Documented .gitlab-ci.yml structure
• Explained Strapi backend setup (env variables, API tokens)
• Covered data management without Strapi admin access (API & seed scripts)
• Added integration workflow (Git push → deploy → data update)
• Included rollback steps and common issues

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🎯 Purpose

• Improve project documentation
• Help developers understand deployment and data flow
• Reduce dependency on Strapi admin panel

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🧪 Testing

• Documentation only (no code changes)

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📎 Notes

Some sections may require further updates based on team confirmation (data handling approach).