feat: Initialize SvelteKit project, add tsconfig.json, and introduce a new Calculator.svelte component.

hdyc-svelte/vite.config.ts

@@ -0,0 +1,6 @@
+import { sveltekit } from '@sveltejs/kit/vite';
+import { defineConfig } from 'vite';
+
+export default defineConfig({
+	plugins: [sveltekit()]
+});