perf: consolidate notif timeStr timers into one global tick; fix osd open-on-start

modules/Backlight.qml

@@ -12,9 +12,12 @@ M.BarSection {
 
     property int percent: 0
     property bool _osdActive: false
+    property bool _ready: false
     readonly property bool _showPanel: root._hovered || hoverPanel.panelHovered || _osdActive
 
-    onPercentChanged: if (percent > 0)
+    Component.onCompleted: _ready = true
+
+    onPercentChanged: if (_ready && percent > 0)
         _flashPanel()
 
     function _flashPanel() {

modules/NotifItem.qml

@@ -29,29 +29,17 @@ QtObject {
         }
     }
 
-    // Relative time string
-    property string timeStr: "now"
-    readonly property Timer _timeStrTimer: Timer {
-        running: root.state !== "dismissed"
-        repeat: true
-        interval: 5000
-        onTriggered: root._updateTimeStr()
-    }
-
-    function _updateTimeStr() {
-        const diff = Date.now() - time;
+    // Relative time string — recomputed whenever NotifService._now ticks (single global 5s timer)
+    readonly property string timeStr: {
+        const diff = M.NotifService._now - time;
         const m = Math.floor(diff / 60000);
-        if (m < 1) {
-            timeStr = "now";
-            return;
-        }
+        if (m < 1)
+            return "now";
         const h = Math.floor(m / 60);
-        if (h < 1) {
-            timeStr = m + "m";
-            return;
-        }
+        if (h < 1)
+            return m + "m";
         const d = Math.floor(h / 24);
-        timeStr = d > 0 ? d + "d" : h + "h";
+        return d > 0 ? d + "d" : h + "h";
     }
 
     function beginDismiss() {

modules/NotifService.qml

@@ -124,6 +124,15 @@ QtObject {
     }
 
     // Persistence
+    // Single global tick for all NotifItem.timeStr bindings — replaces per-item 5s timers
+    property real _now: Date.now()
+    property Timer _nowTimer: Timer {
+        running: root.count > 0
+        repeat: true
+        interval: 5000
+        onTriggered: root._now = Date.now()
+    }
+
     property Timer _saveTimer: Timer {
         interval: 1000
         onTriggered: {

modules/Volume.qml

@@ -39,11 +39,16 @@ M.BarSection {
     }
 
     property bool _osdActive: false
+    property bool _ready: false
     readonly property bool _anyHover: root._hovered || hoverPanel.panelHovered
     readonly property bool _showPanel: _anyHover || _osdActive
 
-    onVolumeChanged: _flashPanel()
-    onMutedChanged: _flashPanel()
+    Component.onCompleted: _ready = true
+
+    onVolumeChanged: if (_ready)
+        _flashPanel()
+    onMutedChanged: if (_ready)
+        _flashPanel()
 
     function _flashPanel() {
         _osdActive = true;