[Feature] Specify lastmod attribute per url link

[Thomas-1985]

Is your feature request related to a problem? Please describe.
No

Describe the solution you'd like
Is there a way to specify the lastmod attribute per url link. So something like this (which can be updated if content changes)

  links: [
    { lang: 'en', url: 'http://test.com/page-1/', lastmod: '2023-01-01' },
    { lang: 'de', url: 'http://test.com/page-1/de/', lastmod: '2023-02-01' }
  ],

This would be extremely helpful