Enable support for rich datatypes in dotnet - isolated based apps using Kafka extension

[raorugan]

Problem : Today dotnet isolated supports only string and string array which is leading to manually deserialize if the topics messages are Avro, JSON or byte arrays[]. This is creating manual effort and perf impact.

Ask : Allow rich data types in isolated worker available for sdks so that all required data types are supported by Kafka.  And there would not be a need to deserialize messages into compatible data types