MetricValue::Custom encoding\decoding support #16945
Description
Is your feature request related to a problem or challenge?
Datafusion 49 brings MetricValue::Custom { name: Cow<'static, str>, value: Arc<dyn CustomMetricValue>,} which can be used to extend metric handling. With datafusion ballista shipping execution metrics from executors to scheduler question it is not clear how can custom value can be encoded/decoded more details about metric serialisation can be found at 1 ? At the moment with the effort to bring datafusion 49 support to ballista 2 we would throw error in case of custom metrics value.
Describe the solution you'd like
We need to provide a clean path to support encoding/decoding of MetricValue::Custom
Describe alternatives you've considered
Alternative approach would be current approach where custom metrics value would trigger error or to be ignored (somehow)
Additional context
No response