feat(home): replace "Why Choose Us" benefits grid with ProofNumbers band

Swaps the soft-adjective benefits section (Rapid Development, Enterprise
Security, Built to Scale, 24/7 Support) for a compact horizontal stat
band so the first below-the-fold surface leads with hard, scannable
numbers instead of generic copy.

- New src/components/ProofNumbers.astro renders 4 large gradient numbers
  with one-line captions: 20+ Projects Delivered, 5★ Client Rating,
  11 Districts Deployed, < 2s Avg Page Load. Numbers carry a TODO for
  stakeholder confirmation; defaults mirror existing hero/stat copy.
- Responsive grid: 2×2 on mobile (<md), 4×1 horizontal band on desktop,
  with subtle vertical dividers between columns on md+.
- Matches site typography tokens (text-secondary-* / text-primary-*)
  with full dark-mode parity (gradients shift to primary-400/300).
- Removes now-unused `benefits` data array and inline SVG icons from
  src/pages/index.astro along with the surrounding section markup.

src/components/ProofNumbers.astro

@@ -0,0 +1,101 @@
+---
+/**
+ * ProofNumbers Component
+ *
+ * A compact horizontal "stat band" rendered between the social-proof logo
+ * strip and the services grid on the homepage. Replaces the older
+ * "Why Choose Us" / "Built for Your Success" benefits grid — the goal is
+ * to lead with hard, scannable proof points instead of soft adjectives.
+ *
+ * Layout:
+ *   - 2 × 2 grid on mobile (<md)
+ *   - 4 × 1 horizontal band on desktop (md+)
+ *
+ * Typography matches the site's existing tokens (text-secondary-* /
+ * text-primary-*) and supports dark mode via Tailwind's `dark:` variants
+ * so the band stays legible under the theme toggle.
+ *
+ * @prop {Array<{ value: string; label: string }>} [items] - override the
+ *        default set of proof points. Each `value` is rendered as the large
+ *        headline number, `label` is the one-line caption underneath.
+ *
+ * NOTE on the default copy: these numbers are placeholder defaults pending
+ * stakeholder confirmation — update them against the latest delivery log
+ * / Google Analytics / Lighthouse run before each release.
+ */
+
+interface ProofItem {
+  value: string;
+  label: string;
+}
+
+interface Props {
+  items?: ProofItem[];
+}
+
+// TODO(content): confirm these proof numbers with the WorkRoot leadership /
+// marketing team before each public release. Defaults reflect the current
+// public-facing claims (hero badge: "20+ teams · 11 districts") plus the
+// performance budget the site is built against (<2s LCP on 4G).
+//
+//  - "20+ Projects Delivered"   — sourced from existing homepage stats array
+//  - "5★ Client Rating"          — every testimonial in this file has
+//                                  rating: 5; tighten to "4.9★" once a
+//                                  weighted average is available
+//  - "11 Districts Deployed"     — matches hero trust badge copy
+//  - "< 2s Avg Page Load"        — performance budget for the marketing site
+//
+// If real audited numbers become available, prefer those over these defaults.
+const defaultItems: ProofItem[] = [
+  { value: '20+', label: 'Projects Delivered' },
+  { value: '5★', label: 'Client Rating' },
+  { value: '11', label: 'Districts Deployed' },
+  { value: '< 2s', label: 'Avg Page Load' },
+];
+
+const { items = defaultItems } = Astro.props;
+// Cap at 4 — the band is designed as a 4×1 / 2×2 layout and extra entries
+// would break the responsive grid. Trim silently rather than overflowing.
+const proofItems = items.slice(0, 4);
+---
+
+<section
+  id="proof-numbers"
+  class="py-16 sm:py-20 bg-white dark:bg-secondary-900 border-y border-secondary-100 dark:border-secondary-800"
+  aria-label="WorkRoot by the numbers"
+>
+  <div class="container-wrapper">
+    <dl
+      class="grid grid-cols-2 md:grid-cols-4 gap-y-10 gap-x-6 sm:gap-x-10 max-w-6xl mx-auto"
+      data-animate="fade-up"
+    >
+      {proofItems.map((item, index) => (
+        <div
+          class:list={[
+            'text-center',
+            // Subtle vertical divider between columns on desktop — keeps the
+            // band feeling like one continuous strip rather than four cards.
+            index > 0
+              ? 'md:border-l md:border-secondary-100 md:dark:border-secondary-800'
+              : '',
+          ]}
+          data-animate="fade-up"
+          data-delay={String(index * 100)}
+        >
+          <dt
+            class="text-4xl sm:text-5xl lg:text-6xl font-bold text-secondary-900 dark:text-secondary-100 tracking-tight leading-none"
+          >
+            <span class="bg-gradient-to-br from-primary-600 to-primary-500 dark:from-primary-400 dark:to-primary-300 bg-clip-text text-transparent">
+              {item.value}
+            </span>
+          </dt>
+          <dd
+            class="mt-3 text-sm sm:text-base font-semibold text-secondary-600 dark:text-secondary-400 uppercase tracking-wider"
+          >
+            {item.label}
+          </dd>
+        </div>
+      ))}
+    </dl>
+  </div>
+</section>