feat(ui): page header actions — Edit (accent) + Revisions menu (view/restore) + Export, top-right

Editor refactored to expose controls; Edit moved into the doc header as the orange
primary action; new Revisions dropdown lists page_revisions with a modal preview + Restore.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

public/views/page.js

@@ -5,6 +5,7 @@ import { markdownEditor } from '../components/markdown_editor.js';
 import { backButton } from '../components/backbtn.js';
 import { breadcrumb } from '../components/breadcrumb.js';
 import { exportMenu } from '../components/export_menu.js';
+import { revisionsMenu } from '../components/revisions_menu.js';
 
 export async function render(main, ctx) {
   const id = ctx.params.id;
@@ -33,11 +34,15 @@ export async function render(main, ctx) {
   mount(main,
     el('div', { class: 'doc-head' },
       el('div', { class: 'doc-head-left' }, backButton(), breadcrumb(page)),
-      exportMenu({ filenameBase: page.slug, getContent: async () => ({ title: page.title, md: page.body_md || '' }) })
+      el('div', { class: 'doc-actions' },
+        revisionsMenu(id, (md) => editor.setValue(md)),
+        editor.controls,
+        exportMenu({ filenameBase: page.slug, getContent: async () => ({ title: page.title, md: editor.value() }) })
+      )
     ),
     el('h1', { class: 'view-h1' }, page.title),
     el('p', { class: 'view-sub muted' }, '/' + page.slug),
-    editor,
+    editor.pane,
     backlinksCard
   );