UPDATE: split the webapp in a widget and the app itself

This splits the webapp in:

* IronCalc (the widget to be published on npmjs)
* The frontend for our "service"
* Adds "dummy code" for the backend using sqlite

webapp/IronCalc/vite.config.ts

@@ -0,0 +1,37 @@
+import { defineConfig } from 'vite';
+import react from '@vitejs/plugin-react';
+import svgr from 'vite-plugin-svgr';
+import { resolve } from 'node:path';
+
+// https://vitejs.dev/config/
+export default defineConfig({
+  build: {
+    lib: {
+      entry: resolve(__dirname, 'src/index.ts'),
+      name: 'IronCalc',
+      // the proper extensions will be added
+      fileName: 'ironcalc',
+    },
+    rollupOptions: {
+      // make sure to externalize deps that shouldn't be bundled
+      // into your library
+      external: ['react', 'react-dom', '@ironcalc/wasm'],
+      output: {
+        // Provide global variables to use in the UMD build
+        // for externalized deps
+        globals: {
+          react: 'React',
+          'react-dom': 'ReactDOM',
+          '@ironcalc/wasm': 'IronCalc',
+        },
+      },
+    },
+  },
+  plugins: [react(), svgr()],
+  server: {
+    fs: {
+      // Allow serving files from one level up to the project root
+      allow: ['..'],
+    },
+  },
+});