feat(preview): add NavigationBlock component, show header in preview

NavigationBlock extracted from navigation/page.tsx into reusable component.
Preview now shows real header (ready: true) as first block — 3 of 8 ready.

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

apps/web/components/blocks/NavigationBlock.tsx

@@ -0,0 +1,83 @@
+export const NAV_ITEMS = [
+  "Клиника",
+  "ЛОР врачи",
+  "Заболевания",
+  "Вопрос-ответ",
+  "ЛОР-операции",
+  "Сурдология",
+  "Цены",
+  "Контакты",
+];
+
+export function NavigationBlock() {
+  return (
+    <div
+      className="overflow-hidden"
+      style={{ border: "1px solid #e5e7eb", boxShadow: "0 1px 4px rgba(0,0,0,0.06)" }}
+    >
+      {/* Топ-бар */}
+      <div
+        className="flex items-center justify-between px-6 py-2 text-xs border-b"
+        style={{ background: "#fff", borderColor: "#e5e7eb", color: "#6b7280" }}
+      >
+        <div className="flex items-center gap-4">
+          <span>📍 Б. Цитная, 3</span>
+          <a href="#" style={{ color: "#0089c3" }}>
+            Клиника ухо горло нос и аллергия
+          </a>
+          <a href="#" style={{ color: "#0089c3" }}>
+            Центр аллергологии и пульмонологии
+          </a>
+        </div>
+        <div className="flex items-center gap-4">
+          <span className="font-bold text-sm" style={{ color: "#111827" }}>
+            /342/ 255-53-84
+          </span>
+          <button className="bb-btn bb-btn-sm bb-btn-pill">Заказать звонок</button>
+        </div>
+      </div>
+
+      {/* Логотип */}
+      <div className="flex items-center px-6 py-3 bg-white">
+        <div className="flex items-center gap-3">
+          <div
+            className="w-10 h-10 rounded-full flex items-center justify-center text-white font-bold text-lg shrink-0"
+            style={{ background: "#0089c3" }}
+          >
+            ✚
+          </div>
+          <div>
+            <div
+              className="text-[11px] font-bold leading-tight uppercase tracking-wide"
+              style={{ color: "#53514e" }}
+            >
+              Клиника<br />ухо, горло, нос
+            </div>
+            <div className="text-[9px] leading-tight mt-0.5" style={{ color: "#9ca3af" }}>
+              им. проф. Е.Н.Оленевой
+            </div>
+          </div>
+        </div>
+      </div>
+
+      {/* Главное меню */}
+      <nav className="flex border-t bg-white" style={{ borderColor: "#e5e7eb" }}>
+        {NAV_ITEMS.map((item, i) => (
+          <a
+            key={item}
+            href="#"
+            className="px-4 py-3 text-sm whitespace-nowrap"
+            style={{
+              color: i === 0 ? "#0089c3" : "#53514e",
+              borderRight: "1px solid #f3f4f6",
+              fontWeight: i === 0 ? 500 : 400,
+              textDecoration: "none",
+            }}
+          >
+            {item}
+          </a>
+        ))}
+      </nav>
+    </div>
+  );
+}