feat(ui): refresh layout, help assets, and panel styling

Update the main template and client scripts for the revised navigation
and zone/device panels, and add bundled help SVG assets under static.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/static/help.js

@@ -7,9 +7,11 @@ document.addEventListener('DOMContentLoaded', () => {
   const mainMenuDropdown = document.getElementById('main-menu-dropdown');
 
   if (helpBtn && helpModal) {
-    helpBtn.addEventListener('click', () => {
+    const openHelp = () => {
       helpModal.classList.add('active');
-    });
+      switchHelpTab('overview');
+    };
+    helpBtn.addEventListener('click', openHelp);
   }
 
   if (helpCloseBtn && helpModal) {
@@ -18,10 +20,37 @@ document.addEventListener('DOMContentLoaded', () => {
     });
   }
 
+  const helpTabButtons = document.querySelectorAll('[data-help-tab]');
+  const helpTabPanels = document.querySelectorAll('[data-help-panel]');
+
+  function switchHelpTab(tabId) {
+    if (!tabId) tabId = 'overview';
+    for (const btn of helpTabButtons) {
+      const on = btn.getAttribute('data-help-tab') === tabId;
+      btn.classList.toggle('active', on);
+      btn.setAttribute('aria-selected', on ? 'true' : 'false');
+    }
+    for (const panel of helpTabPanels) {
+      const on = panel.getAttribute('data-help-panel') === tabId;
+      panel.classList.toggle('active', on);
+      panel.hidden = !on;
+    }
+  }
+
+  for (const btn of helpTabButtons) {
+    btn.addEventListener('click', () => {
+      switchHelpTab(btn.getAttribute('data-help-tab'));
+    });
+  }
+
   // Mobile main menu: forward clicks to existing header buttons
   if (mainMenuBtn && mainMenuDropdown) {
     mainMenuBtn.addEventListener('click', () => {
       mainMenuDropdown.classList.toggle('open');
+      const zonesMenuDropdown = document.getElementById('zones-menu-dropdown');
+      const zonesMenuBtn = document.getElementById('zones-menu-btn');
+      if (zonesMenuDropdown) zonesMenuDropdown.classList.remove('open');
+      if (zonesMenuBtn) zonesMenuBtn.setAttribute('aria-expanded', 'false');
     });
 
     mainMenuDropdown.addEventListener('click', (event) => {