This commit introduces a new PHP file `icons.php` that defines a set of inline SVG icons to replace the Bootstrap Icons webfont. The icons include common UI elements such as calendar, clock, folder, and tag, as well as theme picker icons like sun, moon, snow, droplet, cup, and half. The SVGs are designed to scale with existing font-size rules and are accessible via the `blowdit_icon` function. Additionally, a mapping function `blowdit_theme_icon` is provided to associate theme keys with their corresponding icon names.
- Added new UI strings for theme toggle, copy functionality, and navigation.
- Implemented dynamic theme color for mobile browsers based on user selection.
- Introduced Open Graph and Twitter Card metadata for improved social sharing.
- Added JSON-LD structured data for articles to enhance SEO.
- Created a new JavaScript file for theme behavior, including theme picker, reading progress bar, back-to-top button, and image lightbox functionality.
- Enhanced code blocks with copy-to-clipboard buttons and improved tabbed code block functionality.
- Implemented a random navigation order feature and a table of contents generator for articles.