- Add goavro dependency for Avro schema parsing and decoding
- Implement AvroDecoder with binary data decoding to Go maps
- Add MapToRecordValue() to convert Go values to schema_pb.RecordValue
- Support complex types: records, arrays, unions, primitives
- Add type inference from decoded maps to generate RecordType schemas
- Handle Avro union types and null values correctly
- Comprehensive test coverage including integration tests
This enables conversion of Avro messages to SeaweedMQ format.
