In this PR we add icon buttons in the header to quickly access the my contact page, Forgejo-, and Codeberg profile. I drew a Forgejo and Codeberg logo that I'm not 100% satisfied with. The buttons have a `title` attribute now which explains what the buttons represent. However, I would like to reuse the tooltip hover effect from the contact and about page. These effects are now repeating themselves on both pages, so we should merge them into a partial that can be included on each page, or just load it with the shell element.
<video src="/attachments/12429d26-cbfa-4e63-8ecd-fb1d1d270932" title="Inspelning 2026-04-05 140702" controls></video>
_The `title` tooltip is not visible in the recording, but they're there._
Reviewed-on: https://codeberg.org/vlw/vlw.se/pulls/73
