docs: copy content to new docs engine

[thisthat]

Description

• Copy over the content from the old docs page (docs) to the new page (docs-new).
• Make sure that the front matter form the old pages is replaced with just a markdown h1/# title.
• Make sure that links still work (mkdocs serve or mkdocs build will tell you).
  embed and docsembed hugo shortcodes need to be replaced with {% include "" %}.
• Every folder needs an index.md file which needs to be added where a file doesn't exist yet. Just add a title in there for now.
• The navigation sidebar should be set up in the mkdocs.yml file under the nav: key (check PoC for example). -> will do a follow-up for this so we can discuss

Fixes #2553

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[codecov]

Codecov Report

Merging #2605 (44a2070) into main (fbd4601) will not change coverage.
Report is 1 commits behind head on main.
The diff coverage is n/a.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2605   +/-   ##
=======================================
  Coverage   85.48%   85.48%           
=======================================
  Files         155      155           
  Lines       10175    10175           
=======================================
  Hits         8698     8698           
  Misses       1198     1198           
  Partials      279      279           

Flag	Coverage Δ
certificate-operator	67.43% <ø> (ø)
component-tests	56.36% <ø> (ø)
lifecycle-operator	84.44% <ø> (ø)
metrics-operator	87.43% <ø> (ø)
scheduler	36.53% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

[StackScribe]

Whoops, I started commenting on stuff like stacked headers and I see page titles I don't like but that should not be part of this exercise, right? Make sure that each page has an H1 and we can fix the rest later...

[thisthat]

Whoops, I started commenting on stuff like stacked headers and I see page titles I don't like but that should not be part of this exercise, right? Make sure that each page has an H1 and we can fix the rest later...

@StackScribe yes, we can do a follow-up that fixes these :)
I would be fast in merging this PR and transition everything to the new engine so we don't block other content PR :)

[sonarqubecloud]

SonarCloud Quality Gate failed.   

1 Bug
0 Vulnerabilities
0 Security Hotspots
3 Code Smells

No Coverage information
0.0% Duplication

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