Added a start for the connection abstract class

src/s2python/websocket/connection_client.py

@@ -0,0 +1,36 @@
+from abc import ABC, abstractmethod
+from typing import Any, Dict
+
+class AbstractConnectionClient(ABC):
+    """Abstract class for handling the /requestConnection endpoint."""
+
+    def request_connection(self) -> Any:
+        """Orchestrate the connection request flow: build → execute → handle."""
+        request_data = self.build_connection_request()
+        response_data = self.execute_connection_request(request_data)
+        return self.handle_connection_response(response_data)
+
+    @abstractmethod
+    def build_connection_request(self) -> Dict:
+        """
+        Build the payload for the ConnectionRequest schema.
+        Returns a dictionary with keys: s2ClientNodeId, supportedProtocols.
+        """
+        pass
+
+    @abstractmethod
+    def execute_connection_request(self, request_data: Dict) -> Dict:
+        """
+        Execute the POST request to /requestConnection.
+        Implementations should send the request_data to the endpoint
+        and return the JSON response as a dictionary.
+        """
+        pass
+
+    @abstractmethod
+    def handle_connection_response(self, response_data: Dict) -> Any:
+        """
+        Process the ConnectionDetails response (e.g., extract challenge and connection URI).
+        The response_data contains keys: selectedProtocol, challenge, connectionUri.
+        """
+        pass