[Java][Doc] Define next steps for Arrow Tools module

There are functionalities such as [GenerateSampleData.java](https://github.com/apache/arrow/blob/master/java/vector/src/main/java/org/apache/arrow/vector/GenerateSampleData.java) for example that needs to be reviewed and analyze how this functionality/utility will be related with Arrow Tools module and define a common patter to use for next utilities that are planning to create 

**Reporter**: [David Dali Susanibar Arce](https://issues.apache.org/jira/browse/ARROW-17921) / @davisusanibar

_{**Note**: *This issue was originally created as [ARROW-17921](https://issues.apache.org/jira/browse/ARROW-17921). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}

Start by reviewing java/vector/src/main/java/org/apache/arrow/vector/GenerateSampleData.java and the existing Arrow Tools module. Trace how this utility relates to the module and examine nearby utilities or module guidance. Done means documenting an agreed relationship and a common pattern for future utilities.

Written by the indexing model from the issue text.