Everyone has the Notebooks chooser

From the development repository at 1ccf212.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

client/index.html

@@ -87,13 +87,13 @@
       </label>
     </div>
     <div class="toolbar_right">
-    <div class="group" id="host_tools" hidden>
+    <div class="group" id="host_tools">
       <button id="new_page" type="button"
               data-help="Start a new blank page for everyone. The current page is kept in each notebook.">New</button>
       <button id="load_image" type="button"
               data-help="Put an image file, such as a scanned exercise, on the page for everyone: below the images already there, centred, at its own size. Rest the pen on an image to move it, or near a corner to scale it; it comes to the front. A tap of the eraser on an image removes it; writing on it stays.">Image</button>
       <button id="load_notebook_page" type="button"
-              data-help="Start a new page for everyone from a page kept in a notebook, with everything on it. The current page is kept in each notebook.">Notebooks</button>
+              data-help="Your notebooks and the pages kept in them, to look at or to delete. The host and co-hosts can start a new page for everyone from a kept page, with everything on it; the current page is then kept in each notebook.">Notebooks</button>
     </div>
     <div class="group" aria-label="Notebook">
       <select id="session_notebook" class="notebook_pick" aria-label="Current notebook"