add badges with (plausible) counter

[gernotstarke]

I like to have one of several badges with counters, based upon the plausible.io data.

Please start with the viewer-statistics page on arc42.org, and put the badges in there. We decide later if we use these on other pages too...

plausible.io

They offer an API:

https://plausible.io/docs/stats-api

( I suggest to try out Postman for experiments, they have nice docu on that)

Especially interesting: visitors - The number of unique visitors. pageviews - The number of pageview events.

that would make TWO badges for each of the following sites:

• arc42.org
• arc42.de
• docs.arc42.org
• faq.arc42.org
• quality.arc42.org

Badges via shields.io

See their documentation: https://shields.io/endpoint

[gernotstarke]

imho needs to be done with JavaScript (e.g. fetch() method), but is a rather geeky enhancement.

Currently, let's leave it open

[gernotstarke]

done with status.arc42.org