Adding a sitemap.xml URL for SEO

[msamgan]

Is your feature request related to a problem? Please describe.

SEO required sitemap.xml.

Describe the solution you'd like

a default URL "/sitemap.xml" which will create a sitemap for all the posts.

Describe alternatives you've considered

No response

Additional context

No response

Validations

• [X] Follow our Code of Conduct
• [X] Read the Contributing Guide.
• [X] Check that there isn't already an issue that asks for the same feature to avoid creating a duplicate.