load asciinema locally

[lunchboxav]

Seems like the biggest performance bottleneck of the site is coming from the fact that we embed Asciinema video from external source. Previous effort to load Asciinema locally and serve it from CDN sometimes results in the video mysteriously disappear. If we can solve that issue and run Asciinema file from CDN, it would be awesome.

[lunchboxav]

A result from today's experiment (#172) shows that website loads faster without embedded Asciinema, plus, the performance testing in web.dev increased from 67 to 96. Now we know the biggest culprit.