Embeds contents (see CreateEmbeddedFile(String, ReadOnlySpan<Byte>, PdfEmbeddedFileOptions?)) and lists the new file in the document's
EmbeddedFiles name tree under fileName.
public PdfEmbeddedFileEntry AddEmbeddedFile(string fileName, ReadOnlySpan<byte> contents, PdfEmbeddedFileOptions? options = null)
The file's name and its key in the tree.
The file's bytes; copied.
Media type, description, dates and relationship; null for the defaults.
ISO 32000-2 §7.7.4, Table 32 (PDF 1.4), and §7.11.4. As AddEmbeddedFile(String, PdfFileSpecification).