add top bar

www/app.js

@@ -3,7 +3,6 @@ const el = (id) => document.getElementById(id);
 const statusEl = el("status");
 const listEl = el("lidarList");
 const lidarFormHintEl = el("lidarFormHint");
-const pageTitleEl = document.querySelector(".pageTitle");
 const navItemEls = Array.from(document.querySelectorAll(".navItem[data-page]"));
 const pageOverviewEl = el("pageOverview");
 const pageConfigEl = el("pageConfig");
@@ -134,13 +133,6 @@ function setActivePage(page) {
     if (on) a.setAttribute("aria-current", "page");
     else a.removeAttribute("aria-current");
   });
-  const titles = {
-    dashboard: "Dashboard",
-    config: "Cấu Hình",
-    missions: "Missions",
-    integrations: "Tích hợp",
-  };
-  if (pageTitleEl) pageTitleEl.textContent = titles[p] || "Cấu Hình";
   if (pageOverviewEl) pageOverviewEl.hidden = p !== "dashboard";
   if (pageConfigEl) pageConfigEl.hidden = p !== "config";
   if (pageMissionsEl) pageMissionsEl.hidden = p !== "missions";
@@ -153,7 +145,6 @@ function setActivePage(page) {
     contentEl.classList.toggle("content--missions", p === "missions");
     contentEl.classList.toggle("content--integrations", p === "integrations");
   }
-  if (saveLayoutBtn) saveLayoutBtn.hidden = p !== "config";
   if (p === "missions" && window.MissionsApp) window.MissionsApp.onPageShow();
   else if (window.MissionsApp?.onPageHide) window.MissionsApp.onPageHide();
   if (p === "dashboard" && window.DashboardApp) window.DashboardApp.onPageShow();
@@ -3155,7 +3146,7 @@ async function loadAll() {
   }
 }
 
-el("refreshBtn").addEventListener("click", async () => {
+el("refreshBtn")?.addEventListener("click", async () => {
   try {
     state.viewInitialized = false;
     await loadAll();
@@ -3398,7 +3389,7 @@ window.addEventListener("keyup", (evt) => {
   if (evt.key === "Shift") canvasWrap.classList.remove("shift-pan");
 });
 
-saveLayoutBtn.addEventListener("click", async () => {
+saveLayoutBtn?.addEventListener("click", async () => {
   try {
     await saveCurrentLayout();
     setStatus(`Đã lưu layout «${state.activeLayoutName || ""}»`);