fix: sidebar workspace section → + external-link to /local-workspace

Maintenant au bon endroit: base.html sidebar-section-actions (L229-233)
Pas dans local_workspace.html tree (où il n'était pas visible).
143 tests passent

app/templates/base.html

@@ -229,6 +229,7 @@
         <div class="sidebar-section-actions">
           <button class="section-action-btn" title="New Page" @click.stop="window.FlowDeck.createPage()">{{ fd_icon("file",16) }}</button>
           <button class="section-action-btn" title="New Folder" @click.stop="window.FlowDeck.showCreateFolderModal()">{{ fd_icon("folder",16) }}</button>
+          <a class="section-action-btn" href="/local-workspace" title="Open workspace page" style="text-decoration:none;">{{ fd_icon("external-link",16) }}</a>
         </div>
         {% endif %}
       </div>