[REQ] Option to exclude the comment header in all generated files

Issue Description

There should be an option to exclude the header comment at the beginning of files.

This is making it very difficult to review PRs with very small changes because all the files are affected whenever the version number changes.

Usually we don't commit the generated code but in this case the generator from npm doesn't work and we're using the cli but I don't expect all the developers working on the monorepo to have JRE and the openai-generator-cli installed.

Describe alternatives you've considered

There's a generator called orval that we use for Tanstack ReactQuery client generation and one of the options they offer is to exclude the header comments.
But the client I'm generating is for the backend so I can't use orval in this case

The issue names no files, tests, or entry points. Start by tracing the CLI generation path and where the header comment is added; done means an option can suppress that comment across generated files without removing other generated content, with coverage for the affected generation behavior.