social share link preview improvements

[gerbrent]

When sharing PMS links via social means, the preview is rather mundane but mostly problematic: It's pixelated. Or doesn't exist at all..

I'd like to argue this type of preview can be much improved.

Signal messenger link preview:

Here I think it's just a stretched favicon?

Telegram:

no preview at all..

Element:

---

Preview could look as fancy as:

link to click/share for testing: https://perfectmediaserver.com/06-hardware/new-drive-burnin/

[ironicbadger]

Added https://squidfunk.github.io/mkdocs-material/plugins/social/#layouts-default