(ui) Clarify run action flows

Move run cancellation and review actions out of the page header into
dedicated action panels with clearer operator copy and consistent form
button styling.

Refs #25

src/pobsync_backend/tests/test_views.py

@@ -1667,8 +1667,11 @@ class ViewTests(TestCase):
         response = self.client.get(reverse("run_detail", args=[run.id]))
 
         self.assertEqual(response.status_code, 200)
+        self.assertContains(response, "Run Control")
+        self.assertContains(response, "Cancelling a queued run stops it immediately")
         self.assertContains(response, "Cancel run")
         self.assertContains(response, reverse("cancel_run", args=[run.id]))
+        self.assertContains(response, 'class="danger"', html=False)
 
     def test_run_detail_renders_worker_execution_metadata(self) -> None:
         self.client.force_login(self.staff_user)