✨(demo) new demo

This new demo aims to take advantage of all the new Cunningham's
components. The old demo was kind of a draft, this new one gives
a better overview of what Cunningham is capable of.

apps/demo/cunningham.ts

@@ -1,14 +1,5 @@
 import { Configuration } from "@openfun/cunningham-react";
 
-const config: Configuration = {
-  themes: {
-    default: {
-      components: {
-        button: {
-          "border-radius": "30px",
-        },
-      },
-    },
-  },
-};
-export default config;
+const defaultConfig: Configuration = { themes: {} };
+
+export default defaultConfig;