[R] R6 object documentation doesn't follow best practice

[lazappi]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
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Description

The current Roxygen tags for R6 object created by the R generator do not follow recommended practice. Specifically, R6 methods should not have titles and should not be exported using the @export tag. See the {roxygen2} R6 documentation for an example of what is expected.

This causes problems if users want to create the NAMESPACE file using devtools::document() (which is the common R package development workflow) rather than the generated file as it results in non-existent objects being added to the file.

The template for the main API object also includes information about the methods for each API call but this is redundant as very similar documentation is generated by {roxygen2}, resulting in this information being duplicated in the final help file.

openapi-generator version

7.8.0

OpenAPI declaration file content or url

This problem is with documentation in the template rather than a bug caused by a particular specification

Steps to reproduce

Related issues/PRs

I couldn't find a related issue

Suggest a fix

I will submit a PR updating the template files