fix(service-monitor): toggle 开关点击无响应修复

toggle-slider 的 pointer-events 默认为 auto，遮挡了
label 的点击传递。修复：
- slider 和 slider:before 加 pointer-events: none
- toggle-switch 加 cursor: pointer
- input 加 position: absolute

点击现在穿透 slider 到达 label，再由 label
传递到内部 checkbox input，toggle 正常工作。
Co-Authored-By: Claude <noreply@anthropic.com>

skill/code/web/templates/service_monitor/notification.html

@@ -17,10 +17,10 @@
     .toggle-row { display: flex; align-items: center; justify-content: space-between; padding: 12px 0; border-bottom: 1px solid var(--gray-100); }
     .toggle-row:last-child { border-bottom: none; }
     .toggle-label { font-size: 14px; color: var(--gray-700); }
-    .toggle-switch { position: relative; width: 48px; height: 26px; }
-    .toggle-switch input { opacity: 0; width: 0; height: 0; }
-    .toggle-slider { position: absolute; cursor: pointer; inset: 0; background: var(--gray-300); border-radius: 13px; transition: .2s; }
-    .toggle-slider:before { position: absolute; content: ""; height: 20px; width: 20px; left: 3px; bottom: 3px; background: #fff; border-radius: 50%; transition: .2s; }
+    .toggle-switch { position: relative; width: 48px; height: 26px; cursor: pointer; }
+    .toggle-switch input { opacity: 0; width: 0; height: 0; position: absolute; }
+    .toggle-slider { position: absolute; cursor: pointer; inset: 0; background: var(--gray-300); border-radius: 13px; transition: .2s; pointer-events: none; }
+    .toggle-slider:before { position: absolute; content: ""; height: 20px; width: 20px; left: 3px; bottom: 3px; background: #fff; border-radius: 50%; transition: .2s; pointer-events: none; }
     .toggle-switch input:checked + .toggle-slider { background: var(--primary); }
     .toggle-switch input:checked + .toggle-slider:before { transform: translateX(22px); }
     .btn-test { background: var(--gray-100); color: var(--gray-700); border: 1px solid var(--gray-200); padding: 8px 16px; border-radius: 8px; font-size: 13px; font-weight: 600; cursor: pointer; }