feat!: change package requirements

- Configure as ES module
- Add svelte as peerDependency
- add Vite and vite-preprocess to inline imported SCSS

svelte.config.js

@@ -0,0 +1,16 @@
+import { vitePreprocess as preprocess } from "@sveltejs/vite-plugin-svelte";
+
+const config = {
+  package: {
+    source: "src/carbon-components-svelte",
+  },
+  preprocess: [
+    preprocess({
+      scss: {
+        prependData: '@use "src/variables.scss" as *;',
+      },
+    }),
+  ],
+};
+
+export default config;