docs: add snippet verification for docs/ pages (#2115)

examples/snippets/clients/logging_client.py

@@ -0,0 +1,13 @@
+from mcp import ClientSession, types
+
+
+async def handle_log(params: types.LoggingMessageNotificationParams) -> None:
+    """Handle log messages from the server."""
+    print(f"[{params.level}] {params.data}")
+
+
+session = ClientSession(
+    read_stream,
+    write_stream,
+    logging_callback=handle_log,
+)