Sticky bulk toolbar on dashboard; anchor scroll on device unassign

templates/dashboard.html

@@ -76,7 +76,7 @@
 
   <form method="post" action="{{ url_for('battery_bulk_action') }}" id="bulk-form">
 
-    <div id="bulk-toolbar" style="display:none;margin-bottom:0.75rem;padding:0.6rem 0.75rem;background:#f1f5f9;border-radius:6px;align-items:center;gap:0.5rem;flex-wrap:wrap;">
+    <div id="bulk-toolbar" style="display:none;margin-bottom:0.75rem;padding:0.6rem 0.75rem;background:#f1f5f9;border-radius:6px;align-items:center;gap:0.5rem;flex-wrap:wrap;position:sticky;top:0;z-index:90;box-shadow:0 2px 6px rgba(0,0,0,.08);">
       <span id="selected-count" style="font-size:0.85rem;color:#64748b;margin-right:0.25rem;"></span>
       <button class="btn btn-sm btn-warning" name="action" value="unassign" type="submit">Unassign</button>
       <button class="btn btn-sm btn-secondary" name="action" value="retire" type="submit">Retire</button>

templates/device_detail.html

@@ -92,7 +92,7 @@ function addInstallRow() {
 </script>
 </div>
 
-<div class="card">
+<div class="card" id="installed">
   <h2>Installed Batteries</h2>
   {% set installed = device.batteries | selectattr('status', 'eq', 'installed') | list %}
   {% if installed %}
@@ -109,7 +109,7 @@ function addInstallRow() {
             <td data-label="Notes" class="text-muted">{{ b.notes or '—' }}</td>
             <td data-label="Actions">
               <form class="inline" method="post" action="{{ url_for('battery_unassign', battery_id=b.id) }}">
-                <input type="hidden" name="next" value="{{ url_for('device_detail', device_id=device.id) }}">
+                <input type="hidden" name="next" value="{{ url_for('device_detail', device_id=device.id) }}#installed">
                 <button class="btn btn-sm btn-warning" type="submit">Unassign</button>
               </form>
             </td>