feat: Add comprehensive documentation suite and reorganize project structure

- Created complete documentation in docs/ directory
- Added PROJECT_OVERVIEW.md with feature highlights and getting started guide
- Added ARCHITECTURE.md with system design and technical details
- Added SECURITY.md with comprehensive security implementation guide
- Added DEVELOPMENT.md with development workflows and best practices
- Added DEPLOYMENT.md with production deployment instructions
- Added API.md with complete REST API documentation
- Added CONTRIBUTING.md with contribution guidelines
- Added CHANGELOG.md with version history and migration notes
- Reorganized all documentation files into docs/ directory for better organization
- Updated README.md with proper documentation links and quick navigation
- Enhanced project structure with professional documentation standards

f_scripts/shared/flagicon/flags/1x1/sr.svg

@@ -0,0 +1,6 @@
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+  <path fill="#377e3f" d="M0-.05h512v512.1H0z"/>
+  <path fill="#fff" d="M0 102.37h512v307.26H0z"/>
+  <path fill="#b40a2d" d="M0 153.58h512v204.84H0z"/>
+  <path d="M255.893 163.36l60.2 185.28-157.607-114.51H353.3L195.694 348.64z" fill="#ecc81d"/>
+</svg>