feat: wrap mobile review diffs (#445)

frontend/index.html

@@ -539,6 +539,10 @@
     <div class="review-sheet-body markdown-content" id="review-sheet-body"></div>
     <div class="row"><span class="pill" id="review-ci-state">CI unknown</span><button class="share-work-route" type="button">Share</button><a id="open-review-gitea" href="#" target="_blank" rel="noopener noreferrer">Open in Gitea</a></div>
     <h2>Changed files</h2>
+    <div class="review-display-tools">
+      <button id="review-wrap-lines" type="button" aria-pressed="false" aria-controls="review-files">Wrap lines</button>
+      <span class="small">Keep long diffs inside the review sheet.</span>
+    </div>
     <div id="review-files" class="muted"></div>
     <section class="review-inline-composer" id="review-inline-composer" aria-labelledby="review-inline-title" hidden>
       <strong id="review-inline-title">Comment on changed line</strong>