Add experimental Asciinema support

exampleSite/content.en/docs/shortcodes/asciinema.md

@@ -0,0 +1,28 @@
+# Asciinema
+
+> [!WARNING]
+> Experimental, could change in the future or be removed
+
+Asciinema shortcode integrates asciinema player into the markdown page.
+
+```tpl
+{{</* asciinema
+  cast="asciinema-627097.cast"
+  or
+  cast="https://asciinema.org/a/vJNKUQFjuh7qKI2j3OoaKs8Jk.cast"
+  loop=true
+  autoplay=true
+  speed=2 */>}}
+```
+
+{{< asciinema
+  cast="asciinema-627097.cast"
+  loop=true
+  autoplay=true
+  speed=2 >}}
+
+## Parameters
+
+All parameters added to the shortcode will be transformed to options for Asciinema player, expect `cast` parameter that is used to locate cast file. Cast file follows same rules as portable image, it could be site resource, page resource or remote file URL.
+
+[List of Asciinema options](https://docs.asciinema.org/manual/player/options/)