[WIP] Add Crossmark logo to packtools PDF template

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>indicação de crossmark no packtools</issue_title>
<issue_description>No gerador de PDF

• (packtools) Adicionar logo Crossmark ao template de PDF com link para https://crossmark.crossref.org/dialog?doi={DOI}&domain=pdf - deve ser feito condicionado a um argumento
• (packtools) Criar um modo de adicionar logo Crossmark em arquivos PDF, não necessariamente naqueles gerados pelo gerador de PDF
• (packtools) Incluir metadados XMP no PDF com namespaces crossmark e pdfx:
  • crossmark:DOI, crossmark:MajorVersionDate
  • pdfx:doi, pdfx:CrossmarkMajorVersionDate
  • dc:identifier, prism:doi, prism:url
    </issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes scieloorg/packtools#1116

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