docs(code): add concise docstrings

src/gapido_auth/infrastructure/kavenegar_client.py

@@ -10,17 +10,22 @@ logger = logging.getLogger(__name__)
 
 
 class KavenegarSmsClient(SmsClient):
+    """Kavenegar verify/lookup implementation of the SMS provider strategy."""
+
     def __init__(
         self,
         api_key: str,
         timeout_seconds: float = 10.0,
         transport: httpx.AsyncBaseTransport | None = None,
     ) -> None:
+        """Configure credentials, timeout, and optional test transport."""
         self._api_key = api_key
         self._timeout_seconds = timeout_seconds
         self._transport = transport
 
     async def send_otp(self, mobile: str, code: str, template: str) -> None:
+        """Send an OTP through Kavenegar and raise on transport or API failure."""
+
         url = f"https://api.kavenegar.com/v1/{self._api_key}/verify/lookup.json"
         payload = {"receptor": mobile, "template": template, "token": code, "type": "sms"}
         try: