fix: toggle aria-hidden on modal open/close for screen reader accessibility

static/index.html

@@ -1909,7 +1909,7 @@
        ═══════════════════════════════════════════════════════════════════════ -->
   <div id="tabNavigate" class="tab-panel">
     <div class="detail-header">
-      <button class="back-btn" onclick="closeNavigate()">← Back</button>
+      <button class="back-btn" onclick="navBackToPrevious()">← Back</button>
       <div class="dh-info">
         <div id="navDestName" style="font-size:18px;font-weight:700;">Navigate</div>
         <div id="navDestAddr" style="font-size:12px;color:var(--text2);"></div>
@@ -2373,7 +2373,7 @@
   <!-- ═══════════════════════════════════════════════════════════════════════
        MODAL
        ═══════════════════════════════════════════════════════════════════════ -->
-  <div class="modal-overlay" id="modalOverlay">
+  <div class="modal-overlay" id="modalOverlay" aria-hidden="true">
     <div class="modal" id="modalDialog" role="dialog" aria-modal="true" aria-labelledby="modalTitle">
       <div class="modal-title" id="modalTitle">Confirm</div>
       <div class="modal-body" id="modalBody">Are you sure?</div>
@@ -2920,7 +2920,9 @@
 
       // Save focus and show
       modalFocusRestore = document.activeElement;
-      document.getElementById('modalOverlay').classList.add('open');
+      const overlay = document.getElementById('modalOverlay');
+      overlay.setAttribute('aria-hidden', 'false');
+      overlay.classList.add('open');
 
       // Focus the right element
       if (opts.type === 'prompt') {
@@ -2937,7 +2939,9 @@
     }
 
     function resolveModal(value) {
-      document.getElementById('modalOverlay').classList.remove('open');
+      const overlay = document.getElementById('modalOverlay');
+      overlay.classList.remove('open');
+      overlay.setAttribute('aria-hidden', 'true');
       if (modalResolve) {
         // For form type, collect input values
         if (modalType === 'form') {
@@ -4639,7 +4643,10 @@
     async function navigateToAsset() {
       if (!AppState.currentAssetId) return;
       if (!AppState.gpsLat || !AppState.gpsLng) {
-        showToast('GPS location not available. Tap ◎ My Location first.', true);
+        showToast('GPS location not available — enable location access to navigate', true);
+        // Still go to navigate tab to show the GPS warning UI
+        AppState._navData = null;
+        switchTab('tabNavigate');
         return;
       }
       try {
@@ -4818,24 +4825,40 @@
         const clearBtn = document.getElementById('clearNavSearch');
         if (clearBtn) clearBtn.style.display = q ? '' : 'none';
         if (!q) { results.innerHTML = ''; return; }
+
+        const hasGPS = !!(AppState.gpsLat && AppState.gpsLng);
+
         try {
           const assets = await api('/api/assets?q=' + encodeURIComponent(q) + '&limit=8');
+
+          // Build results header with GPS status
+          let html = '';
+          if (!hasGPS) {
+            html += '<div style="font-size:12px;color:var(--amber);padding:4px 4px 8px;">📍 GPS off — straight-line routing only · <span style="text-decoration:underline;cursor:pointer;" onclick="reEnableGPS()">enable</span></div>';
+          }
+
           if (!assets.length) {
-            results.innerHTML = '<div class="empty-state" style="padding:12px;">No assets found</div>';
+            html += '<div class="empty-state" style="padding:12px;">No assets found</div>';
+            results.innerHTML = html;
             return;
           }
-          results.innerHTML = assets.map(a => {
+
+          html += assets.map(a => {
             const hasLocation = a.latitude != null && a.longitude != null;
-            return `<div class="asset-item" style="${hasLocation ? '' : 'opacity:0.5;'}" 
-              onclick="navToSearchedAsset(${a.id})">
-              <div class="ai-icon cat-${cssSafe(a.category)}">📍</div>
+            const canNavigate = hasLocation && hasGPS;
+            const clickAttr = canNavigate ? ` onclick="navToSearchedAsset(${a.id})" style="cursor:pointer;"` : ' style="opacity:0.45;cursor:default;"';
+            const badge = !hasLocation ? '⚠ No GPS' : (!hasGPS ? '📍' : '🧭');
+            return `<div class="asset-item"${clickAttr}>
+              <div class="ai-icon cat-${cssSafe(a.category)}">${catIcon(a.category)}</div>
               <div class="ai-info">
                 <div class="ai-name">${esc(a.name)}</div>
-                <div class="ai-meta">${esc(a.machine_id || '')} ${hasLocation ? '📍 ' + esc(a.address || 'GPS tagged') : '⚠ No location'}</div>
+                <div class="ai-meta">${esc(a.machine_id || '')} · ${badge} ${hasLocation ? esc(a.address || 'GPS tagged') : 'No coordinates'}</div>
               </div>
-              <div class="ai-arrow">→</div>
+              <div class="ai-arrow">${canNavigate ? '→' : ''}</div>
             </div>`;
           }).join('');
+
+          results.innerHTML = html;
         } catch (e) {
           results.innerHTML = '<div class="empty-state" style="padding:12px;">Search failed</div>';
         }
@@ -4853,9 +4876,12 @@
     async function navToSearchedAsset(assetId) {
       // Fetch asset details to get navigation data
       if (!AppState.gpsLat || !AppState.gpsLng) {
-        showToast('GPS location not available. Tap ◎ My Location first.', true);
+        showToast('GPS location not available — enable location access to navigate', true);
         return;
       }
+      // Show loading feedback
+      const btn = document.querySelector(`#navSearchResults .asset-item[onclick*="${assetId}"]`);
+      if (btn) btn.style.opacity = '0.5';
       try {
         const nav = await api('/api/assets/' + assetId +
           '/navigation?lat=' + AppState.gpsLat + '&lng=' + AppState.gpsLng);