🎨 Isolate infra and ui components

The src/base.rs is still to be reworked.

src/ui/components/avatar_selector.scss

@@ -0,0 +1,17 @@
+.avatar-selector {
+	position: relative;
+	height: 100%;
+	aspect-ratio: 1;
+
+    &__picture {
+		$height: 65%;
+		$margin: calc(100% - $height) / 2;
+
+        position: absolute;
+	    height: $height;
+	    aspect-ratio: 1;
+
+		top: $margin;
+		right: $margin;
+    }
+}