Fix CI failures: remove unicode and fix lean build

- Replace all unicode (emojis, checkmarks, arrows, em-dashes) with ASCII in .claude/ docs
- Comment out OperatingSystemsList route in core.js - breaks lean builds without computers plugin
- Comment out Operating Systems tab in ModelCatalogHub
- TODO: Plugins should dynamically register their settings routes

Fixes #2 CI check failures on wj branch

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

frontend/src/views/settings/ModelCatalogHub.vue

@@ -27,13 +27,14 @@
       >
         Models
       </router-link>
-      <router-link
+      <!-- TODO: Operating Systems tab should be added by computers plugin -->
+      <!-- <router-link
         :to="{ name: 'model-catalog-os' }"
         class="tab"
         :class="{ active: $route.name === 'model-catalog-os' }"
       >
         Operating Systems
-      </router-link>
+      </router-link> -->
     </div>
 
     <div class="tab-content">