fix: Update @method decorators and type hints for dbus-next compatibility

Co-authored-by: aider (gemini/gemini-2.5-pro) <aider@aider.chat>

main.py

@@ -28,46 +28,46 @@ class Agent(ServiceInterface):
     def __init__(self, interface_name):
         super().__init__(interface_name)
 
-    @method()
+    @method
     def Release(self):
         logging.info('Agent Released')
 
-    @method(in_signature='o', out_signature='s')
-    def RequestPinCode(self, device: 'o') -> 's':
+    @method
+    def RequestPinCode(self, device: str) -> str:
         logging.info(f"RequestPinCode for {device}, returning static PIN")
         return "0000"
 
-    @method(in_signature='o', out_signature='u')
-    def RequestPasskey(self, device: 'o') -> 'u':
+    @method
+    def RequestPasskey(self, device: str) -> int:
         logging.info(f"RequestPasskey for {device}")
         return 0
 
-    @method(in_signature='ouq', out_signature='')
-    def DisplayPasskey(self, device: 'o', passkey: 'u', entered: 'q'):
+    @method
+    def DisplayPasskey(self, device: str, passkey: int, entered: int):
         logging.info(f"DisplayPasskey for {device}: {passkey}")
 
-    @method(in_signature='os', out_signature='')
-    def DisplayPinCode(self, device: 'o', pincode: 's'):
+    @method
+    def DisplayPinCode(self, device: str, pincode: str):
         logging.info(f"DisplayPinCode for {device}: {pincode}")
 
-    @method(in_signature='ou', out_signature='')
-    def RequestConfirmation(self, device: 'o', passkey: 'u'):
+    @method
+    def RequestConfirmation(self, device: str, passkey: int):
         logging.info(f"RequestConfirmation for {device} with passkey {passkey}")
         # Automatically confirm and trust
         loop = asyncio.get_event_loop()
         loop.create_task(trust_and_connect_device(device))
 
-    @method(in_signature='o', out_signature='')
-    def RequestAuthorization(self, device: 'o'):
+    @method
+    def RequestAuthorization(self, device: str):
         logging.info(f"RequestAuthorization for {device}")
         pass
 
-    @method(in_signature='os', out_signature='')
-    def AuthorizeService(self, device: 'o', uuid: 's'):
+    @method
+    def AuthorizeService(self, device: str, uuid: str):
         logging.info(f"AuthorizeService for {device} with uuid {uuid}")
         pass
 
-    @method()
+    @method
     def Cancel(self):
         logging.info('Pairing Cancelled')