fix(ui): delete prompts use data-confirm, so a quote in a name no longer runs script (#5099)

#5099 "A name containing a quote runs script when an admin clicks Delete".
Inline handlers like onclick="return confirm('Delete {{ rule.name }}?')" are
HTML-decoded before the JavaScript is parsed, so autoescaping did not stop a
name such as  x');fetch(…);//  from running.

- Every prompt (22 handlers, plus the docker prune and token revoke ones)
  is now data-confirm="…", read through dataset by one submit listener in
  base.html; nothing rendered is parsed as JavaScript.
- The remaining inline handlers take integers only (|int), and the time
  range buttons pass this.dataset.range.
- tests/test_inline_handlers.py fails on any {{ }} in an inline handler that
  is not |int, with a self-test; tests/_templates.py is the one template
  walker the template guards now share.

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

steward/templates/dashboard/share.html

@@ -32,7 +32,7 @@
             </div>
           </div>
           <form method="post" action="/d/{{ dashboard.id }}/share/revoke/{{ token.id }}"
-                style="margin:0;" onsubmit="return confirm('Revoke this share link?')">{{ csrf_field() }}
+                style="margin:0;" data-confirm="Revoke this share link?">{{ csrf_field() }}
             <button type="submit" class="btn btn-danger btn-sm">Revoke</button>
           </form>
         </div>