fix(ui): Integrate webhooks panel into status panel

The webhooks panel was appearing separately from the status panel.
Now it's properly nested inside the status-panel div:

- Moved webhooks-section inside status-panel in HTML
- Updated CSS so nested webhooks looks like a subsection (no double borders)
- Simplified JS toggle logic - webhooks shows/hides automatically with status panel
- Admin users see webhooks inside status panel, collapsed by default

public/style.css

@@ -1528,6 +1528,16 @@ body {
   overflow: hidden;
 }
 
+/* When nested inside status-panel, remove outer styling and look like a subsection */
+.status-panel > .webhooks-section {
+  background: transparent;
+  border: none;
+  border-radius: 0;
+  box-shadow: none;
+  margin-bottom: 0;
+  border-top: 1px solid var(--border);
+}
+
 .webhooks-header {
   padding: 16px 20px;
   background: var(--surface-alt);