fix(nosignal): square notification toasts + guard lock screen.name

- Notification toasts: square the cards + round urgency/icon badges
  (Tokens.rounding.full ignored rounding.scale) and hide/flatten the notifsBg
  blob (deformAmount 0, radius 0, opacity 0) so toasts are flat square cards.
- LockSurface: guard screen?.name to silence a transient init warning.

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

modules/drawers/ContentWindow.qml

@@ -209,6 +209,9 @@ StyledWindow {
             id: notifsBg
 
             panel: panels.notifications
+            deformAmount: 0 // NoSignal: square notification toasts
+            radius: 0
+            opacity: 0 // toasts draw their own square cards
         }
 
         PanelBg {

modules/lock/LockSurface.qml

@@ -26,8 +26,8 @@ WlSessionLockSurface {
 
     readonly property bool errored: root.pam.state === "error" || root.pam.state === "fail"
 
-    contentItem.Config.screen: screen.name
+    contentItem.Config.screen: screen?.name ?? ""
-    contentItem.Tokens.screen: screen.name
+    contentItem.Tokens.screen: screen?.name ?? ""
 
     color: "transparent"
 

modules/notifications/Content.qml

@@ -63,7 +63,7 @@ Item {
         anchors.rightMargin: root.clampedPadding
 
         color: "transparent"
-        radius: Tokens.rounding.large
+        radius: 0
 
         StyledListView {
             id: list

modules/notifications/Notification.qml

@@ -23,7 +23,7 @@ StyledRect {
     property bool expanded: Config.notifs.openExpanded
 
     color: root.modelData.urgency === NotificationUrgency.Critical ? Colours.palette.m3secondaryContainer : Colours.tPalette.m3surfaceContainer
-    radius: Tokens.rounding.large
+    radius: 0
 
     implicitHeight: inner.implicitHeight
 
@@ -116,7 +116,7 @@ StyledRect {
                 visible: root.hasImage || root.hasAppIcon
 
                 sourceComponent: StyledClippingRect {
-                    radius: Tokens.rounding.full
+                    radius: 0
                     color: root.modelData.urgency === NotificationUrgency.Critical ? Colours.palette.m3error : root.modelData.urgency === NotificationUrgency.Low ? Colours.layer(Colours.palette.m3surfaceContainerHighest, 2) : Colours.palette.m3secondaryContainer
                     implicitWidth: TokenConfig.sizes.notifs.image
                     implicitHeight: TokenConfig.sizes.notifs.image
@@ -147,7 +147,7 @@ StyledRect {
                 anchors.bottom: root.hasImage ? image.bottom : undefined
 
                 sourceComponent: StyledRect {
-                    radius: Tokens.rounding.full
+                    radius: 0
                     color: root.modelData.urgency === NotificationUrgency.Critical ? Colours.palette.m3error : root.modelData.urgency === NotificationUrgency.Low ? Colours.layer(Colours.palette.m3surfaceContainerHighest, 2) : Colours.palette.m3secondaryContainer
                     implicitWidth: root.hasImage ? Tokens.sizes.notifs.badge : TokenConfig.sizes.notifs.image
                     implicitHeight: root.hasImage ? Tokens.sizes.notifs.badge : TokenConfig.sizes.notifs.image
@@ -358,7 +358,7 @@ StyledRect {
                 implicitHeight: expandIcon.implicitHeight
 
                 StateLayer {
-                    radius: Tokens.rounding.full
+                    radius: 0
                     color: root.modelData.urgency === NotificationUrgency.Critical ? Colours.palette.m3onSecondaryContainer : Colours.palette.m3onSurface
                     onClicked: root.expanded = !root.expanded
                 }