[client] Fix stuck Windows tray dark icon on state change (#6532)

Only the connected state passed a dark variant to SetDarkModeIcon, so
on dark Windows themes the connected-dark icon stuck for connecting,
error and update-* states. Pass a dark variant for every state.

client/ui/icons.go

@@ -18,18 +18,30 @@ var iconDisconnected []byte
 //go:embed assets/netbird-systemtray-connecting.png
 var iconConnecting []byte
 
+//go:embed assets/netbird-systemtray-connecting-dark.png
+var iconConnectingDark []byte
+
 //go:embed assets/netbird-systemtray-error.png
 var iconError []byte
 
+//go:embed assets/netbird-systemtray-error-dark.png
+var iconErrorDark []byte
+
 //go:embed assets/netbird-systemtray-needs-login.png
 var iconNeedsLogin []byte
 
 //go:embed assets/netbird-systemtray-update-connected.png
 var iconUpdateConnected []byte
 
+//go:embed assets/netbird-systemtray-update-connected-dark.png
+var iconUpdateConnectedDark []byte
+
 //go:embed assets/netbird-systemtray-update-disconnected.png
 var iconUpdateDisconnected []byte
 
+//go:embed assets/netbird-systemtray-update-disconnected-dark.png
+var iconUpdateDisconnectedDark []byte
+
 //go:embed assets/netbird-systemtray-connected-macos.png
 var iconConnectedMacOS []byte
 

client/ui/tray_icon.go

@@ -119,18 +119,18 @@ func (t *Tray) iconForState() (icon, dark []byte) {
 	// Windows: colored PNGs.
 	switch {
 	case connecting:
-		return iconConnecting, nil
+		return iconConnecting, iconConnectingDark
 	case errored:
-		return iconError, nil
+		return iconError, iconErrorDark
 	case needsLogin:
-		return iconNeedsLogin, nil
+		return iconNeedsLogin, iconNeedsLogin
 	case connected && hasUpdate:
-		return iconUpdateConnected, nil
+		return iconUpdateConnected, iconUpdateConnectedDark
 	case connected:
 		return iconConnected, iconConnectedDark
 	case hasUpdate:
-		return iconUpdateDisconnected, nil
+		return iconUpdateDisconnected, iconUpdateDisconnectedDark
 	default:
-		return iconDisconnected, nil
+		return iconDisconnected, iconDisconnected
 	}
 }