Integrate LFX charts onto the website

[castrojo]

Ok I'd like to flex our LFX usage more:

https://insights.linuxfoundation.org/project/ublue-os-bluefin/contributors?timeRange=past90days&start=2025-06-03&end=2025-09-01

Would be cool to get some of these on the site. Putting this badge in the footer somewhere classy would be cool too:

But we don't need to overdo it, we have https://docs.projectbluefin.io/analytics as a dedicated page.