Update K8s docs homepage

[evilnick]

Done

• Reworked the landing page to standardise on diataxis layout.

QA

• Check out this feature branch
• Run the site using the command ./run serve or dotrun
• View the site locally in your web browser at: http://0.0.0.0:8001/
  • Be sure to test on mobile, tablet and desktop screen sizes

[webteam-app]

Demo starting at https://ubuntu-com-13230.demos.haus

[codecov]

Codecov Report

Merging #13230 (67f31fd) into main (2cc24d9) will not change coverage.
Report is 2 commits behind head on main.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main   #13230   +/-   ##
=======================================
  Coverage   75.31%   75.31%           
=======================================
  Files         106      106           
  Lines        2840     2840           
  Branches      929      929           
=======================================
  Hits         2139     2139           
  Misses        679      679           
  Partials       22       22           

[carkod]

LGTM

[anthonydillon]

@evilnick none of these links work or seem to have destinations to go to.

@carkod did you check the links?

Can we revert this change or update the links please?

[evilnick]

sorry, this all got a bit messy - the pages they link to are in #13254