feat: initial Speedboard implementation

sitespeed.io web UI with Express/Pug/SQLite — port 3132.
Includes job queue, SSE live log, full metrics dashboard,
site history, CO2/axe/CWV sections, and Docker support.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

routes/site.js

@@ -0,0 +1,14 @@
+import { Router } from 'express';
+import { getSiteHistory } from '../db.js';
+
+const router = Router();
+
+router.get('/', (req, res) => {
+  const url = req.query.url;
+  if (!url) return res.redirect('/history');
+
+  const jobs = getSiteHistory(url, 20);
+  res.render('site', { title: `Site History — ${url}`, url, jobs });
+});
+
+export default router;