Add network stats to SystemMonitor, fix ActiveWindow text display

SystemMonitor: add network up/down stats (also added setting to disable
it in BarTab)
ActiveWindow: add elide if not hovered

Services/SystemStatService.qml

@@ -14,6 +14,21 @@ Singleton {
   property real memoryUsageGb: 0
   property real memoryUsagePer: 0
   property real diskUsage: 0
+  property real rxSpeed: 0
+  property real txSpeed: 0
+
+  // Helper function to format network speeds
+  function formatSpeed(bytesPerSecond) {
+    if (bytesPerSecond < 1024) {
+      return bytesPerSecond.toFixed(0) + " B/s"
+    } else if (bytesPerSecond < 1024 * 1024) {
+      return (bytesPerSecond / 1024).toFixed(1) + " KB/s"
+    } else if (bytesPerSecond < 1024 * 1024 * 1024) {
+      return (bytesPerSecond / (1024 * 1024)).toFixed(1) + " MB/s"
+    } else {
+      return (bytesPerSecond / (1024 * 1024 * 1024)).toFixed(1) + " GB/s"
+    }
+  }
 
   // Background process emitting one JSON line per sample
   Process {
@@ -29,6 +44,8 @@ Singleton {
           root.memoryUsageGb = data.memgb
           root.memoryUsagePer = data.memper
           root.diskUsage = data.diskper
+          root.rxSpeed = parseFloat(data.rx_speed) || 0
+          root.txSpeed = parseFloat(data.tx_speed) || 0
         } catch (e) {
 
           // ignore malformed lines