release: v3.0.0

[demyanovs]

Added

• Support for <pre><code> pattern (in addition to <pre>) for better Markdown compatibility
• Support for class="language-*" attribute on <code> tag for language detection
• Fluent interface for showLineNumbers() and showActionPanel() methods
• HighlighterFactory class for creating highlighter instances based on language
• CodeBlockWrapper class for separating presentation logic from highlighting
• LanguageNormalizer class for normalizing language identifiers with aliases support
• Custom exceptions: InvalidLanguageException, InvalidThemeException, ThemeNotSetException
• PHP as default language for code blocks without specified language
• Comprehensive test suite

Changed

• BREAKING: Removed Singleton pattern from all highlighter classes (HighlighterPHP, HighlighterXML, HighlighterBash)
• BREAKING: Made HighlighterBase an abstract class (cannot be instantiated directly)
• BREAKING: Added ext-dom PHP extension requirement (previously optional with regex fallback)
• Improved HTML attribute parsing using DOMDocument with regex fallback
• Enhanced syntax highlighting logic in HighlighterBase
• Improved XML/HTML highlighting: fixed line-by-line processing, proper attribute highlighting
• Updated PHPDoc comments throughout the codebase

Fixed

• Fixed issue with extra empty lines at the beginning and end of code blocks
• Fixed line numbering