centurion: seed child headset kind via pairing_info

The construction-time kind=headset seeding only covered the direct
create_device path. G522-style devices reach a CenturionReceiver,
whose notify_devices() builds the headset as a child Device with
device_info=None and sets dev.centurion=True only after __init__ —
so the __init__ guard never fired and the child kept kind=None.

Set kind=headset in the pairing_info dict the receiver already passes
into Device.__init__, which covers the bridge path. Both paths now
seed the kind offline.

lib/logitech_receiver/centurion.py

@@ -35,6 +35,7 @@ from solaar import configuration
 from . import base
 from . import exceptions
 from . import hidpp10
+from . import hidpp10_constants
 from .centurion_constants import CenturionCoreFeature
 from .common import Alert
 from .common import Battery
@@ -376,7 +377,7 @@ class CenturionReceiver:
         # Create child Device with receiver=self, number=1
         pairing_info = {
             "wpid": self.product_id,
-            "kind": None,
+            "kind": hidpp10_constants.DEVICE_KIND.headset,  # every Centurion-transport device so far is a headset
             "serial": None,
             "polling": None,
             "power_switch": None,

tests/logitech_receiver/test_hidpp20_complex.py

@@ -1213,6 +1213,21 @@ def test_centurion_receiver_container_with_device():
         recv[2]
 
 
+def test_centurion_receiver_child_device_kind_headset():
+    """notify_devices() seeds the headset child with kind=headset via pairing_info,
+    so the headphone icon shows even when the headset is powered off at startup."""
+    info = FakeCenturionDeviceInfo(product="PRO X 2 LIGHTSPEED")
+    recv = CenturionReceiver(FakeLowLevel(), 0x99, info)
+    recv._pending = False
+    recv._dongle_features = []
+
+    recv.notify_devices()
+
+    child = recv[1]
+    child.online = False
+    assert child.kind == "headset"
+
+
 def test_centurion_receiver_enable_connection_notifications():
     """CenturionReceiver.enable_connection_notifications() returns False."""
     info = FakeCenturionDeviceInfo()