Everyone has the Notebooks chooser

From the development repository at 1ccf212.

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

client/js/main.js

@@ -1053,7 +1053,10 @@ async function enterSession(invitationText, name, notebook) {
 
   // The host drives: the host starts new pages, and may let a guest do so.
   function showHostTools() {
-    element('host_tools').hidden = !session.mayMakePages();
+    // New and Image are the host's; Notebooks, in the same group so that
+    // nothing moves for the host, is everyone's (the chooser reserves
+    // loading).
+    for (const id of ['new_page', 'load_image']) element(id).hidden = !session.mayMakePages();
     // The Hide tool is for the host and co-hosts; losing the right
     // while it is chosen puts the pen back in hand.
     const hideTool = /** @type {HTMLElement} */ (document.querySelector('[data-tool=hide]'));
@@ -1095,7 +1098,7 @@ async function enterSession(invitationText, name, notebook) {
     // A deleted notebook leaves the toolbar's list.
     showNotebooks(sessionPicker).catch(() => {});
   });
-  element('load_notebook_page').addEventListener('click', () => { chooser.open(writer.notebook); });
+  element('load_notebook_page').addEventListener('click', () => { chooser.open(writer.notebook, session.mayMakePages()); });
 
   // Image files are chosen, and pictures of the page exported, through a
   // chooser of our own, which begins where the notebooks are.