Fix: Handle items with unmatched categories in showItemsStep

Items were being grouped only by known categories. If the category
array was empty or didn't include an item's category, those items
never got checkboxes rendered, causing confirmItems() to filter
them all out.

Now collects unassigned items and groups them by their category
name (or 'Menu' as fallback).

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

portal/setup-wizard.html

@@ -2647,10 +2647,29 @@
 
       // Group items by category
       let itemsByCategory = {};
+      let assignedItemIds = new Set();
+
       categories.forEach(cat => {
-        itemsByCategory[cat.name] = items.filter(item => item.category === cat.name);
+        const catItems = items.filter(item => item.category === cat.name);
+        if (catItems.length > 0) {
+          itemsByCategory[cat.name] = catItems;
+          catItems.forEach(item => assignedItemIds.add(item.id));
+        }
       });
 
+      // Collect any items not assigned to a known category
+      const unassignedItems = items.filter(item => !assignedItemIds.has(item.id));
+      if (unassignedItems.length > 0) {
+        // Group by their category name, or "Menu" if none
+        unassignedItems.forEach(item => {
+          const catName = item.category || 'Menu';
+          if (!itemsByCategory[catName]) {
+            itemsByCategory[catName] = [];
+          }
+          itemsByCategory[catName].push(item);
+        });
+      }
+
       let itemsHtml = '';
       for (const [catName, catItems] of Object.entries(itemsByCategory)) {
         if (catItems.length === 0) continue;