docs: add MaterialApp meta

Signed-off-by: Florian-Schoenherr <[email protected]>

Author: Florian-Schoenherr

packages/docs/src/routes/components/material-app.md

@@ -1,5 +1,7 @@
 ---
 title: Material App
+description: The material app component is a wrapper which provides all components inside it with styles and helpers
+keywords: material app, svelte materialify material component, svelte material component
 related:
   - getting-started/installation
   - getting-started/usage