Create documentation for contributors

This is a sub-issue of #15

Overview

Develop comprehensive documentation to guide contributors on how to submit new blog posts to our platform.

Tasks

• Write CONTRIBUTING_BLOGS.md guide with clear step-by-step instructions
• Create a blog post template file (blog-template.md) with example frontmatter
• Document all required and optional frontmatter fields with descriptions
• Provide examples for common Markdown formatting elements (headings, lists, code blocks)
• Include guidance on image inclusion and optimization
• Document the full contribution workflow (fork → create → submit PR)
• Add troubleshooting section for common issues

Contents for CONTRIBUTING_BLOGS.md

1. Introduction and purpose
2. Prerequisites (GitHub account, basic Markdown knowledge)
3. Step-by-step contribution process
4. Frontmatter fields reference
5. Markdown formatting guidelines
6. Media inclusion guidelines
7. Sample blog post examples
8. Submission checklist
9. Troubleshooting

Definition of Done

• Documentation is clear, comprehensive, and beginner-friendly
• Blog template file is created and well-commented
• All frontmatter fields are properly documented
• Media handling instructions are clear with examples
• Documentation is reviewed for accuracy and completeness