add third-party animation plugin to docs

docs/_sidebar.md

@@ -44,5 +44,6 @@
   - [Global App State](/plugins/global_app_state.md)
   - [Storage](/plugins/storage.md)
   - [Custom Plugins](/plugins/custom_plugins.md)
+  - [Animation](/plugins/animation.md)
 - Performance
   - [Lazy loading](/performance/lazy-loading.md)

docs/plugins/animation.md

@@ -0,0 +1,7 @@
+# Animation plugin
+
+The Animation plugin is a third-party plugin for creating and controlling animations in Blits applications. It supports both sequential animations and timeline-based animations, with configurable easing, delays, repeats, and lifecycle callbacks.
+
+The plugin is maintained by a third party and is not part of the Blits core package.
+
+For installation instructions, examples, and the complete API reference, see the [Blits Animation Plugin documentation](https://blits-animation-plugin.bravaapps.com/).

docs/sidebar.json

@@ -189,6 +189,10 @@
       {
         "text": "Custom Plugins",
         "link": "/plugins/custom_plugins"
+      },
+      {
+        "text": "Animation",
+        "link": "/plugins/animation"
       }
     ]
   },