fix: inherit DesignSystem AppWindow->palette

gallery/Main.qml

@@ -12,18 +12,6 @@ AppWindow {
     visible: true
     title: qsTr("flowy - gallery")
 
-    palette {
-        accent: Theme.accent
-        dark: Theme.foreground
-        window: Theme.background
-        windowText: Theme.foreground
-        base: Theme.muted
-        brightText: Theme.muted
-        text: Theme.foreground
-        button: Theme.accent
-        buttonText: "#FFFFFF"
-    }
-
     ColumnLayout {
       anchors.left: parent.left
       anchors.right: parent.right