Memory page and search inside chats, files and memory (Ctrl+K, GET /search)

The account's memory as the web's Settings -> Memory keeps it: add, change,
remove, over /api/v2/memories. Ctrl+K asks the server's search once two
letters are typed and lists the hits below the titles, the matched ranges
drawn as <mark> elements over plain text.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ui/index.html

@@ -54,6 +54,7 @@
         <button type="button" class="navrow" id="nav-scheduled" data-view="scheduled"><span class="navrow__icon"></span><span data-i18n>Scheduled</span></button>
         <button type="button" class="navrow" id="nav-files" data-view="files"><span class="navrow__icon"></span><span data-i18n>Files</span></button>
         <button type="button" class="navrow" id="nav-archived" data-view="archived"><span class="navrow__icon"></span><span data-i18n>Archived</span></button>
+        <button type="button" class="navrow" id="nav-memory" data-view="memory"><span class="navrow__icon"></span><span data-i18n>Memory</span></button>
       </div>
       <ul class="list" id="chat-list" aria-label="Chats" data-i18n-aria-label></ul>
       <div class="side__foot">
@@ -133,6 +134,15 @@
       <div class="page__body" id="archived-body"></div>
     </section>
 
+    <section class="page" id="page-memory" hidden aria-labelledby="memory-title">
+      <header class="head">
+        <h1 class="head__title" id="memory-title" data-i18n>Memory</h1>
+        <div class="head__place"></div>
+        <div class="head__tools"><button type="button" class="tool" id="memory-refresh" aria-label="Read again" title="Read again" data-i18n-aria-label data-i18n-title></button></div>
+      </header>
+      <div class="page__body" id="memory-body"></div>
+    </section>
+
     <section class="page settings" id="settings" hidden aria-labelledby="settings-title">
       <header class="head">
         <h1 class="head__title" id="settings-title" data-i18n>Settings</h1>