Line wrap toggle for editor and paste viewer with remembered preference (#130)

- wrap toggle button on /new editor and paste view (accent active state)
- flips white-space pre <-> pre-wrap on the code body
- shared localStorage preference palette-wrap, default off
- settings checkbox reads and writes the same preference

internal/web/templates/new.html

@@ -22,6 +22,9 @@
       <div class="gutter" id="gutter">1</div>
       <textarea class="editor" id="content" placeholder="Paste your code, text, or notes here…" spellcheck="false"></textarea>
     </div>
+    <div class="editor-tools">
+      <button class="iconbtn wrap-toggle" id="wrap-toggle" type="button" title="Toggle line wrap" aria-label="Toggle line wrap" aria-pressed="false">wrap</button>
+    </div>
     <div class="created-banner" id="created"></div>
     <div class="actionbar">
       <span class="hint">Ctrl+Enter to create</span>
@@ -291,5 +294,25 @@ window.addEventListener('pageshow', e => {
 document.addEventListener('keydown', e => {
   if ((e.ctrlKey || e.metaKey) && e.key === 'Enter') { e.preventDefault(); create(); }
 });
+
+// #130: line wrap toggle, shared preference with the viewer (palette-wrap)
+(function () {
+  var el = document.getElementById('content');
+  var btn = document.getElementById('wrap-toggle');
+  function apply(on) {
+    el.classList.toggle('wrap', on);
+    btn.setAttribute('aria-pressed', on ? 'true' : 'false');
+  }
+  var on = false;
+  try { on = localStorage.getItem('palette-wrap') === 'true'; } catch (e) {}
+  apply(on);
+  btn.addEventListener('click', function () {
+    on = !on;
+    try { localStorage.setItem('palette-wrap', on ? 'true' : 'false'); } catch (e) {}
+    apply(on);
+  });
+  // follow changes made in settings on other tabs/pages
+  document.addEventListener('palette-wrapchange', function (e) { apply(e.detail); });
+})();
 </script>
 {{template "foot" .}}