Initial scaffold: FastAPI server, responsive UI shell

static/app.js

@@ -0,0 +1,17 @@
+// Command Center SPA Router
+const sections = document.querySelectorAll('.panel');
+const links = document.querySelectorAll('.nav-links a');
+
+function navigate(hash) {
+    const target = hash.replace('#', '') || 'agents';
+    sections.forEach(s => s.hidden = s.id !== target);
+    links.forEach(l => l.classList.toggle('active', l.getAttribute('href') === '#' + target));
+}
+
+links.forEach(l => l.addEventListener('click', e => {
+    e.preventDefault();
+    window.location.hash = l.getAttribute('href');
+}));
+
+window.addEventListener('hashchange', () => navigate(window.location.hash));
+navigate(window.location.hash || '#agents');