fix: bump annotation-viewer.js cache buster to v4

Browser was serving stale cached version without editor format
support (objects array). Bumped ?v=4 on all three templates:
recipe_preview, task_execute, task_editor.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/templates/measure/task_execute.html

@@ -521,7 +521,7 @@
   pdfjsLib.GlobalWorkerOptions.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/3.11.174/pdf.worker.min.js';
 </script>
 <script src="{{ url_for('static', filename='js/numpad.js') }}"></script>
-<script src="{{ url_for('static', filename='js/annotation-viewer.js') }}"></script>
+<script src="{{ url_for('static', filename='js/annotation-viewer.js') }}?v=4"></script>
 <script src="{{ url_for('static', filename='js/caliper.js') }}"></script>
 
 <script>