avro_to_arrow: Support in memory apache_avro Value's

### Is your feature request related to a problem or challenge?

I have Avro values in memory parsed using the apache_avro crate. I would like to convert these and get a RecordBatch.

### Describe the solution you'd like

Currently AvroArrowArrayReader is private and the avro_to_arrow::Reader only accepts a io reader and calls the apache_avro reader internally. I would have to currently serialize my in memory values and pass the bytes to avro_to_arrow::Reader.

### Describe alternatives you've considered

_No response_

### Additional context

I have a fork with a hacky fix, I can make a draft PR if but the API was a bit weird with the lifetime the apache_avro::Reader required

Start by reading the private AvroArrowArrayReader and the public avro_to_arrow::Reader, focusing on how the apache_avro::Reader lifetime is currently handled. Define an API that accepts in-memory apache_avro values and produces a RecordBatch without serializing them; done means callers can use parsed values directly.

Written by the indexing model from the issue text.