Add label range filter (two inputs) to dashboard

templates/dashboard.html

@@ -129,6 +129,10 @@
     </select>
     <input type="text" id="filter-text" oninput="applyFilters()" placeholder="Search…"
            style="padding:0.25rem 0.5rem;font-size:0.85rem;border:1px solid #cbd5e1;border-radius:4px;width:140px;">
+    <input type="number" id="filter-range-from" oninput="applyFilters()" placeholder="# from"
+           style="padding:0.25rem 0.5rem;font-size:0.85rem;border:1px solid #cbd5e1;border-radius:4px;width:70px;">
+    <input type="number" id="filter-range-to" oninput="applyFilters()" placeholder="# to"
+           style="padding:0.25rem 0.5rem;font-size:0.85rem;border:1px solid #cbd5e1;border-radius:4px;width:70px;">
     <button type="button" id="select-all-btn" onclick="mobileSelectAll()" class="btn btn-sm btn-secondary" style="display:none;">Select all</button>
     <button type="button" onclick="resetFilters()" class="btn btn-sm btn-secondary" id="filter-reset" style="display:none;">✕ Reset</button>
     <span id="filter-count" style="font-size:0.8rem;color:#64748b;"></span>
@@ -219,7 +223,7 @@
         </thead>
         <tbody>
           {% for b in batteries %}
-          <tr data-brand="{{ b.brand }}" data-size="{{ b.size or '' }}" data-status="{{ b.status }}" data-storage="{{ b.storage_location or '' }}">
+          <tr data-brand="{{ b.brand }}" data-size="{{ b.size or '' }}" data-status="{{ b.status }}" data-storage="{{ b.storage_location or '' }}" data-label="{{ b.label }}">
             <td data-label=""><input type="checkbox" name="battery_ids" value="{{ b.id }}" class="row-cb"></td>
             <td data-label="Label" data-sort-col="label" data-sort="{{ b.label }}"><a href="{{ url_for('battery_detail', battery_id=b.id) }}"><strong>{{ b.label }}</strong></a></td>
             <td data-label="Brand" data-sort-col="brand" data-sort="{{ b.brand }}">{{ b.brand }}</td>
@@ -371,7 +375,11 @@ function applyFilters() {
   var size    = document.getElementById('filter-size').value;
   var storage = document.getElementById('filter-storage').value;
   var text    = document.getElementById('filter-text').value.trim().toLowerCase();
-  var anyActive = (status && status !== 'active') || brand || size || storage || text;
+  var rangeFromVal = document.getElementById('filter-range-from').value.trim();
+  var rangeToVal   = document.getElementById('filter-range-to').value.trim();
+  var rangeMin = rangeFromVal !== '' ? parseInt(rangeFromVal, 10) : null;
+  var rangeMax = rangeToVal   !== '' ? parseInt(rangeToVal,   10) : null;
+  var anyActive = (status && status !== 'active') || brand || size || storage || text || rangeFromVal || rangeToVal;
   document.getElementById('filter-reset').style.display = anyActive ? '' : 'none';
 
   var rows = document.querySelectorAll('tbody tr[data-brand]');
@@ -387,6 +395,14 @@ function applyFilters() {
     if (size    && row.dataset.size    !== size)     show = false;
     if (storage && row.dataset.storage !== storage)  show = false;
     if (text    && row.textContent.toLowerCase().indexOf(text) === -1) show = false;
+    if (rangeMin !== null || rangeMax !== null) {
+      var lbl = row.dataset.label || '';
+      var m = lbl.match(/(\d+)\s*$/);
+      var n = m ? parseInt(m[1], 10) : null;
+      if (n === null) show = false;
+      else if (rangeMin !== null && n < rangeMin) show = false;
+      else if (rangeMax !== null && n > rangeMax) show = false;
+    }
     row.dataset.filteredOut = show ? '' : '1';
     if (show) filtered++;
   });
@@ -468,6 +484,8 @@ function resetFilters() {
     document.getElementById(id).value = '';
   });
   document.getElementById('filter-text').value = '';
+  document.getElementById('filter-range-from').value = '';
+  document.getElementById('filter-range-to').value = '';
   applyFilters();
 }