Extend the licenserecon job to be a generic "copyright review" job that can help NEW queue processing

Thanks to @aquilamacedo recent work, we now have a licenserecon job available in Salsa CI. Running lrc helps validate that the debian/copyright roughly covers all files and licenses match the copyright headers in the files. We could, however, rename this job into a generic copyright job and extend what it does and perhaps promote a practice that package maintainers would run this job and read its output after every new upstream version import, or at least before uploading something going to the NEW queue.

In the March 2025 newgateway idea @plessy wrote relevant CI code and a checklist.

I believe the FTP Masters team also has some documentation about copyright review, but the only doc I found so far was the ftp-new man page. At ftp-master.debian.org there is the NEW queue checklist and the REJECT-FAQ that mention several copyright related requirements/checks that could perhaps be automated, or at least easier to for a package maintainer to self-review if CI printed out some findings.

No matter who implements this, it needs to have active review/approval from the @ftp-team to ensure that whatever the CI reports is aligned with the actual requirements to pass the NEW queue.