wails/v3/internal/templates/sveltekit/frontend/vite.config.js

import { sveltekit } from '@sveltejs/kit/vite';
import { defineConfig, searchForWorkspaceRoot } from 'vite';

export default defineConfig({
    server: {
        fs: {
          allow: [
            // search up for workspace root
            searchForWorkspaceRoot(process.cwd()),
            // your custom rules
            './bindings/*',
          ],
        },
    },
	plugins: [sveltekit()]
});