mdvu v0.3.1

Added

• Application Menu Dialect Switcher (View → Dialect):
  • Integrated Dialect submenu in macOS View menu offering:
    • Generic (CommonMark)
    • GitHub (GFM)
    • Obsidian
  • Active dialect displays checkmark state (NSControl.StateValue.on).
  • Selecting a dialect immediately re-renders the document and preserves scroll ratio.
• Automated Dialect Detection (YAML Frontmatter & Directives):
  • Added MarkdownDocumentDirective parser that scans:
    • YAML frontmatter keys: dialect, markdown-dialect, markdown_dialect, mode (supporting obsidian, github, gfm, generic, commonmark).
    • Top-of-file HTML comment directives (e.g. <!-- dialect: obsidian -->, Run: mdvu --dialect obsidian, Open in Obsidian dialect).
  • Dynamic hierarchy: explicit CLI --dialect and explicit user menu selection override document directives; default .generic allows document directives to activate automatically.
• Preservation of Raw <style> Elements:
  • <style>...</style> blocks in Markdown are preserved during sanitization instead of being escaped as literal text, allowing custom single-page layouts, showcase templates, and responsive stylesheets to render as intended.
  • <script> elements and event handler attributes remain strictly disarmed.
• Showcase Fixture & High-Resolution Snapshot:
  • Added test-onescreen.md fixture validating multi-column card presentations, native MathML, embedded base64 wiki-embeds, and diagram pipelines.
  • Added Tests/Snapshots/MDVu.jpg high-resolution showcase screenshot linked in README.md.

Changed

• Compiler Intermediate Hygiene:
  • Thin LTO .bc bitcode files generated during release and benchmark compilation are isolated inside Tests/ and ignored by git, eliminating root-level workspace clutter.
• Temporary Render Lifecycle:
  • Unique PID-scoped temporary directory for rendered HTML documents with automatic cleanup on document close and application shutdown.