notifs: add close button

Closes #220

modules/notifications/Notification.qml

@@ -413,13 +413,29 @@ StyledRect {
                 Anim {}
             }
 
+            Action {
+                modelData: QtObject {
+                    readonly property string text: qsTr("Close")
+                    function invoke(): void {
+                        root.modelData.notification.dismiss();
+                    }
+                }
+            }
+
             Repeater {
                 model: root.modelData.actions
 
-                delegate: StyledRect {
+                delegate: Component {
+                    Action {}
+                }
+            }
+        }
+    }
+
+    component Action: StyledRect {
         id: action
 
-                    required property NotificationAction modelData
+        required property var modelData
 
         radius: Appearance.rounding.full
         color: root.modelData.urgency === NotificationUrgency.Critical ? Colours.palette.m3secondary : Colours.palette.m3surfaceContainerHigh
@@ -450,19 +466,16 @@ StyledRect {
         TextMetrics {
             id: actionTextMetrics
 
-                        text: modelData.text
+            text: action.modelData.text
             font.family: actionText.font.family
             font.pointSize: actionText.font.pointSize
             elide: Text.ElideRight
             elideWidth: {
-                            const numActions = root.modelData.actions.length;
+                const numActions = root.modelData.actions.length + 1;
                 return (inner.width - actions.spacing * (numActions - 1)) / numActions - Appearance.padding.normal * 2;
             }
         }
     }
-            }
-        }
-    }
 
     component Anim: NumberAnimation {
         duration: Appearance.anim.durations.normal