chore: use orjson in streaming event JSON serialisation for performance improvement (#24763)

api/libs/orjson.py

@@ -0,0 +1,11 @@
+from typing import Any, Optional
+
+import orjson
+
+
+def orjson_dumps(
+    obj: Any,
+    encoding: str = "utf-8",
+    option: Optional[int] = None,
+) -> str:
+    return orjson.dumps(obj, option=option).decode(encoding)