feat: update package.json and add generate-barrel script

- Set project name to "nova-design-system" and updated version to 0.1.0
- Added description for the project
- Defined exports for the main entry and styles
- Included a new script "barrel" to generate index.ts for components
- Added "sass" as a devDependency

chore: update package-lock.json

- Added "sass" as a devDependency with version ^1.99.0
- Updated dependencies including @parcel/watcher and others

refactor: remove unused assets and Welcome component

- Deleted astro.svg and background.svg assets
- Removed Welcome.astro component as it was no longer needed

scripts/generate-barrel.mjs

@@ -0,0 +1,42 @@
+/**
+ * Scans src/components/ and regenerates src/components/index.ts.
+ * Each component folder must have an index.ts that exports the component.
+ * Run: npm run barrel
+ */
+
+import { readdir, writeFile, stat } from 'fs/promises';
+import { join, resolve } from 'path';
+import { fileURLToPath } from 'url';
+
+const __dirname = fileURLToPath(new URL('.', import.meta.url));
+const componentsDir = resolve(__dirname, '../src/components');
+const outputFile = join(componentsDir, 'index.ts');
+
+const entries = await readdir(componentsDir);
+
+const componentFolders = (
+  await Promise.all(
+    entries.map(async (name) => {
+      const fullPath = join(componentsDir, name);
+      const info = await stat(fullPath);
+      return info.isDirectory() ? name : null;
+    })
+  )
+).filter(Boolean);
+
+if (componentFolders.length === 0) {
+  console.log('No component folders found.');
+  process.exit(0);
+}
+
+const lines = [
+  '// Auto-generated by scripts/generate-barrel.mjs — do not edit manually.',
+  '',
+  ...componentFolders.map((name) => `export * from './${name}/index.ts';`),
+  '',
+];
+
+await writeFile(outputFile, lines.join('\n'), 'utf-8');
+
+console.log(`Barrel generated with ${componentFolders.length} component(s):`);
+componentFolders.forEach((name) => console.log(`  - ${name}`));