Add batched status endpoint and optimize frontend performance

Server-side batched /api/v1/services/status endpoint replaces N
individual browser probes with a single API call (HEAD-first with
GET fallback, concurrency-limited, CA-aware HTTPS agent).

Frontend: clock reuses DOM instead of rebuilding innerHTML every
second with drift-correcting timer that pauses on hidden tabs.
Card animations use CSS transitionDelay + requestAnimationFrame.
Internet dot blink moved from JS intervals to CSS keyframes with
prefers-reduced-motion support. Service worker rewritten with
network-first navigation, stale-while-revalidate assets, and
navigation preload. Font faces drop TTF fallbacks, use font-display
swap.

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

status/js/core/init.js

@@ -25,14 +25,28 @@
   function animateTopCards() {
     const topCards = document.querySelectorAll('.top .card');
     topCards.forEach((card, index) => {
-      card.style.opacity = '0';
-      card.style.transform = 'translateY(20px)';
-      setTimeout(() => {
-        card.style.transition = 'opacity 0.3s cubic-bezier(0.4, 0, 0.2, 1), transform 0.3s cubic-bezier(0.4, 0, 0.2, 1)';
-        card.style.opacity = '1';
-        card.style.transform = 'translateY(0)';
-      }, index * 150); // 150ms delay between top cards
+      card.style.transitionDelay = `${Math.min(index * 60, 300)}ms`;
     });
+    requestAnimationFrame(() => {
+      topCards.forEach(card => card.classList.add('loaded'));
+    });
+  }
+
+  function registerServiceWorker() {
+    if (!('serviceWorker' in navigator)) return;
+    if (!window.isSecureContext && location.hostname !== 'localhost' && location.hostname !== '127.0.0.1') return;
+
+    const register = () => {
+      navigator.serviceWorker.register('/sw.js', { updateViaCache: 'none' }).catch((error) => {
+        console.warn('[init] Service worker registration failed:', error);
+      });
+    };
+
+    if (document.readyState === 'complete') {
+      register();
+    } else {
+      window.addEventListener('load', register, { once: true });
+    }
   }
 
   // Initialize dashboard (called after TOTP gate check or directly if TOTP disabled)
@@ -184,6 +198,7 @@
 
   window.initializeDashboard = initializeDashboard;
   window.loadCustomServices = loadCustomServices;
+  registerServiceWorker();
 
   // TOTP-gated initialization
   (async () => {