Update available tag.

src/js/updater.js

@@ -0,0 +1,38 @@
+// ── UPDATE CHECKER ────────────────────────────────────────────────────────────
+(async function checkForUpdate() {
+  try {
+    const [localRes, remoteRes] = await Promise.all([
+      fetch('version.json'),
+      fetch('https://api.github.com/repos/Johnnybegood90/GridTV/releases/latest')
+    ]);
+    if (!localRes.ok || !remoteRes.ok) return;
+
+    const local  = (await localRes.json()).version  ?? '0.0.0';
+    const remote = (await remoteRes.json()).tag_name ?? '0.0.0';
+
+    const clean = v => v.replace(/^v/, '');
+    const toNum = v => v.split('.').map(Number);
+
+    const [lMaj, lMin, lPat] = toNum(clean(local));
+    const [rMaj, rMin, rPat] = toNum(clean(remote));
+
+    const hasUpdate =
+      rMaj > lMaj ||
+      (rMaj === lMaj && rMin > lMin) ||
+      (rMaj === lMaj && rMin === lMin && rPat > lPat);
+
+    if (!hasUpdate) return;
+
+    const badge = document.createElement('a');
+    badge.className  = 'update-badge';
+    badge.href       = `https://github.com/Johnnybegood90/GridTV/releases/latest`;
+    badge.target     = '_blank';
+    badge.rel        = 'noopener';
+    badge.textContent = `${L.update_available} ${clean(remote)}`;
+    badge.title      = L.update_title;
+
+    document.querySelector('.topbar')?.appendChild(badge);
+  } catch (_) {
+    // Silencieux — pas de connexion ou rate limit GitHub
+  }
+})();