Async Css Loading

[jasperf]

This PR implements asynchronous CSS loading to improve page performance by deferring non-critical stylesheets, allowing the browser to render content faster without being blocked by CSS downloads. The implementation adds WordPress filters to modify how stylesheets are loaded, converting standard blocking <link> tags to use the media="print" swap technique for async loading. Additionally, this PR includes a significant documentation cleanup, removing 21 documentation files that were either outdated, redundant, or better consolidated elsewhere in the project.

Performance Optimization:

• Added async CSS loading filters in app/filters.php to defer non-critical stylesheet loading using the print media swap technique
• Modified app/setup.php to support the new async loading behavior for theme stylesheets
• Updated theme version in style.css to reflect the new release

Documentation Cleanup:

• Removed 21 documentation files from the docs/ directory, including block-specific guides, integration documentation, and development references
• Deleted files covering ACF blocks, WooCommerce integration, content layout guides, and individual block documentation
• This cleanup removes approximately 12,900 lines of potentially outdated documentation to reduce maintenance burden

Changelog:

• Updated CHANGELOG.md to document the async CSS loading feature and related changes

Files Changed:

• CHANGELOG.md (Modified)
• app/filters.php (Modified)
• app/setup.php (Modified)
• style.css (Modified)
• 10 files deleted from docs/ directory
• 12 files deleted from docs/blocks/ directory