Support link preview (public activities)

User story: Dave from Robin Foods has been using public activities feature and wants them to be more easily viewed (link preview) when sharing them in Telegram groups

Here’s an example of how it looks like

from Log: incoming feedback in raw format - #3 by bruno

Complexity: Support link previews · Issue #2617 · karrot-dev/karrot-frontend · GitHub

Outcomes (or what needs to be done to move forward): work on it :rofl: