Bracket the widget with whitespace so it groups with Offscale

Adds a trailing spacer to match the leading one, so Offscale + agents read
as their own group rather than running into the bluetooth/network/audio run.

Bar sections lay out with spacing: 0, so this can only come from slack the
widget reserves itself. Bluetooth already contributes ~11px of leading slot
slack; the spacer adds to that, taking the gap from ~13px to ~31px.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Panel.qml

@@ -452,6 +452,16 @@ Panel {
         else root.toggle()
       }
     }
+
+    // Trailing counterpart to the leading spacer, so Offscale + agents read as
+    // their own group rather than running into the bluetooth/network/audio run.
+    // Bluetooth already contributes ~11px of leading slot slack; this adds to
+    // it rather than replacing it.
+    Item {
+      width: Style.space(9)
+      height: 1
+      anchors.verticalCenter: parent.verticalCenter
+    }
   }
 
   KeyboardPanel {