fix(nosignal): notification toasts — below the bar + no blob curve

- Position the toast wrapper at y:46 so toasts clear the 38px NsBar (they were
  overlapping it; caelestia's Content negates the wrapper top margin, so the
  offset must be on the wrapper's y, not its margin).
- Fully collapse the notifsBg blob (visible:false + implicitWidth/Height 0) —
  opacity/visible alone don't hide a BlobGroup member, which left a rounded
  corner peeking under the square card.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

modules/drawers/ContentWindow.qml

@@ -211,7 +211,10 @@ StyledWindow {
             panel: panels.notifications
             deformAmount: 0 // NoSignal: square notification toasts
             radius: 0
-            opacity: 0 // toasts draw their own square cards
+            opacity: 0
+            visible: false
+            implicitWidth: 0 // collapse the blob entirely (toasts draw their own square cards)
+            implicitHeight: 0
         }
 
         PanelBg {

modules/drawers/Panels.qml

@@ -70,7 +70,7 @@ Item {
         sessionPanel: sessionWrapper
         utilitiesPanel: utilities
 
-        anchors.top: parent.top
+        y: 46 // NoSignal: drop the toasts below the 38px NsBar (+ gap)
         anchors.right: parent.right
     }