Add new features and refactor project structure
- Added cmd/main.go for the main application entry point.
- Implemented PNG to PDF conversion in internal/converter/pngToPdf.go.
- Added SVG to PNG conversion in internal/converter/svgToPng.go.
- Created SVG handler in internal/handlers/svg_handler.go.
- Removed outdated main.go file.
- Moved and renamed index.html to web/index.html for better organization.