- Add cdnjs.cloudflare.com, fonts.googleapis.com, and fonts.gstatic.com to connect-src CSP directive
- Add waitForHljs helper function with 50 attempt limit and 100ms polling interval
- Check if hljs is defined before highlighting code blocks in popout view
- Fall back to async waiting if hljs not immediately available to prevent undefined reference errors
- Import CodeMirror 6 modules via ESM with importmap for @codemirror/state
- Add editor modal UI with header, cancel/save buttons, and editor body container
- Implement openEditor function to load file content and initialize CodeMirror with language-specific syntax highlighting
- Support 20+ file extensions including markdown, python, javascript, html, css, json, xml, sql, php, cpp, java, rust, and shell scripts
