Fix translation key in node detail page: nodes.tags → entities.tags

The Tags panel title was showing 'nodes.tags' as literal text instead of the translation.

Fixed: node-detail.js line 174 now uses entities.tags

Comprehensive review completed:
- Verified all 115 unique translation keys across all pages
- All keys properly resolve to valid translations in en.json
- All i18n tests passing

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

src/meshcore_hub/web/static/js/spa/pages/node-detail.js

@@ -171,7 +171,7 @@ ${heroHtml}
 
     <div class="card bg-base-100 shadow-xl">
         <div class="card-body">
-            <h2 class="card-title">${t('nodes.tags')}</h2>
+            <h2 class="card-title">${t('entities.tags')}</h2>
             ${tagsTableHtml}
             ${adminTagsHtml}
         </div>