Rename 'Add Asset' tab to 'Add / Find Asset' across nav + tabs

- Drawer nav: 'Add Asset' → 'Add / Find Asset'
- Bottom tab bar: 'Add Asset' → 'Add / Find Asset'
- Updated e2e_browser_test.py assertions to match

static/index.html

@@ -878,7 +878,7 @@
     </div>
     <nav class="drawer-nav">
       <button class="dn-item active" data-tab="tabAddAsset" onclick="navFromDrawer('tabAddAsset')">
-        <span class="dn-icon">📷</span> Add Asset
+        <span class="dn-icon">📷</span> Add / Find Asset
       </button>
       <button class="dn-item" data-tab="tabAssets" onclick="navFromDrawer('tabAssets')">
         <span class="dn-icon">📦</span> Asset List
@@ -1396,7 +1396,7 @@
        ═══════════════════════════════════════════════════════════════════════ -->
   <div class="tabs">
     <button class="tab-btn active" data-tab="tabAddAsset" onclick="switchTab('tabAddAsset')">
-      <span class="tab-icon">📷</span> Add Asset
+      <span class="tab-icon">📷</span> Add / Find Asset
     </button>
     <button class="tab-btn" data-tab="tabAssets" onclick="switchTab('tabAssets')">
       <span class="tab-icon">📦</span> Assets