Add theme toggle, hero snippet, and reorganize homepage components

- Set up next-themes with a light/dark toggle in the header and move all
  sections onto theme tokens; dark mode stays pure black
- Replace the hero terminal line with the AI Elements Snippet component
- Restructure components into layout/, sections/, and shared/ with
  site-wide config in lib/site.ts

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

components/sections/stats-section.tsx

@@ -0,0 +1,32 @@
+import { StatsGlobe } from '@/components/sections/stats/stats-globe';
+import { Container } from '@/components/shared/container';
+
+const stats = [
+  { value: '45ms', label: 'Median edge response, worldwide' },
+  { value: '99.99%', label: 'Platform uptime over the last year' },
+  { value: '35+', label: 'Frameworks supported out of the box' },
+  { value: '1.2T', label: 'Requests served every month' },
+];
+
+export function StatsSection() {
+  return (
+    <section className="relative overflow-hidden border-y border-border bg-background py-16 sm:py-24">
+      <StatsGlobe />
+      <Container className="relative z-10 grid grid-cols-2 gap-px px-0 lg:grid-cols-4">
+        {stats.map((stat) => (
+          <div
+            key={stat.label}
+            className="px-6 py-12 text-center ring-1 ring-border"
+          >
+            <div className="text-4xl font-semibold tracking-tight sm:text-5xl">
+              {stat.value}
+            </div>
+            <div className="mx-auto mt-3 max-w-[16ch] text-sm text-foreground/45">
+              {stat.label}
+            </div>
+          </div>
+        ))}
+      </Container>
+    </section>
+  );
+}