refactor: enhance TimerPage layout and functionality; update theme and tokens for improved design consistency

- Refactored TimerPage component to improve layout and user experience.
- Updated theme configuration to utilize design tokens for better maintainability.
- Introduced new tokens for colors and typography to align with design principles.
- Simplified state management and improved timer functionality.
- Enhanced accessibility and responsiveness of UI elements.

desktop/kadence_desktop/qml/components/GhostButton.qml

@@ -0,0 +1,29 @@
+// The outlined button, for everything that is not the primary action.
+import QtQuick
+import QtQuick.Controls
+
+import ".."
+
+Button {
+    id: control
+    implicitHeight: 34
+    leftPadding: 14
+    rightPadding: 14
+
+    background: Rectangle {
+        radius: 8
+        color: control.hovered ? Qt.alpha(Theme.ember, 0.07) : "transparent"
+        border.width: 1
+        border.color: control.hovered ? Theme.ember : Theme.rule
+        Behavior on color { ColorAnimation { duration: 110 } }
+    }
+    contentItem: Label {
+        text: control.text
+        color: control.enabled ? Theme.ink : Theme.faint
+        font.pixelSize: 13
+        font.weight: Font.Medium
+        font.family: Theme.sansFamily
+        horizontalAlignment: Text.AlignHCenter
+        verticalAlignment: Text.AlignVCenter
+    }
+}