feat: build IPTEK company website with full bilingual support

- Complete Next.js 16 app with App Router: Home, About, Products, Contact, Privacy pages
- Product detail pages: ZappCare, Unified TMS, EMR Clinic
- Bilingual support (Indonesian/English) via LanguageContext + translations.ts
- Language switcher pill button (🇮🇩 ID / 🇬🇧 EN) in Navbar with localStorage persistence
- Navbar with logo, responsive mobile menu, translated nav links
- Contact form with captcha, server action email sending, translated labels
- Material Design 3 color tokens, Manrope + Inter fonts, Material Symbols icons
- Local product image assets and company logo

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

app/privacy/BackButton.tsx

@@ -0,0 +1,16 @@
+"use client";
+
+import { useRouter } from "next/navigation";
+
+export default function BackButton() {
+  const router = useRouter();
+  return (
+    <button
+      onClick={() => router.back()}
+      className="inline-flex items-center gap-2 text-primary font-bold hover:gap-4 transition-all duration-300"
+    >
+      <span className="material-symbols-outlined">arrow_back</span>
+      <span>Back</span>
+    </button>
+  );
+}