Initial commit: code playground with multi-framework support

Express + SQLite backend with Monaco editor frontend.
Supports HTML/CSS/JS, TypeScript, React (JSX/TSX), Vue SFC,
and Svelte with live preview, console output, save/fork/share.

Includes CSS preprocessors (SCSS, Less), framework-specific
compilation (Babel, TypeScript, Svelte compiler), and
CDN-loaded runtime libraries for preview rendering.

server.js

@@ -0,0 +1,48 @@
+import express from 'express';
+import { nanoid } from 'nanoid';
+import { stmts } from './db.js';
+
+const app = express();
+app.use(express.json());
+app.use(express.static('public'));
+
+// API: Create fiddle
+app.post('/api/fiddles', (req, res) => {
+  const id = nanoid(10);
+  const { title = 'Untitled', html = '', css = '', css_type = 'css', js = '', js_type = 'javascript' } = req.body;
+  try {
+    stmts.insert.run({ id, title, html, css, css_type, js, js_type });
+    res.json({ id, title, html, css, css_type, js, js_type });
+  } catch (e) {
+    res.status(500).json({ error: e.message });
+  }
+});
+
+// API: List recent fiddles
+app.get('/api/fiddles', (_req, res) => {
+  res.json(stmts.list.all());
+});
+
+// API: Get fiddle
+app.get('/api/fiddles/:id', (req, res) => {
+  const fiddle = stmts.get.get(req.params.id);
+  if (!fiddle) return res.status(404).json({ error: 'Not found' });
+  res.json(fiddle);
+});
+
+// API: Update fiddle
+app.put('/api/fiddles/:id', (req, res) => {
+  const existing = stmts.get.get(req.params.id);
+  if (!existing) return res.status(404).json({ error: 'Not found' });
+  const { title = existing.title, html = existing.html, css = existing.css, css_type = existing.css_type, js = existing.js, js_type = existing.js_type || 'javascript' } = req.body;
+  stmts.update.run({ id: req.params.id, title, html, css, css_type, js, js_type });
+  res.json({ id: req.params.id, title, html, css, css_type, js, js_type });
+});
+
+// SPA route: serve index.html for /f/:id
+app.get('/f/:id', (_req, res) => {
+  res.sendFile('index.html', { root: 'public' });
+});
+
+const port = process.env.PORT || 3000;
+app.listen(port, () => console.log(`Fiddle server running on http://localhost:${port}`));