Dynamic Month & Year into Posts 1.8.1

Fixed: Recurring February 29 countdowns now produce the same valid leap-day result in PHP and the browser.
Fixed: Invalid countdown dates no longer display as zero days, and the default day label is plural-aware.
Fixed: WP-CLI accepts both complete plugin shortcodes and date types with named options.
Improved: Added WordPress 7.1 compatibility, content-role block metadata, current dependency security fixes and wider runtime checks.
Improved: Corrected countdown, editor, cache, pattern and WP-CLI documentation.