Docs/cluster peering 1.15 updates (#16291) (#16410)

* initial commit

* initial commit

* Overview updates

* Overview page improvements

* More Overview improvements

* improvements

* Small fixes/updates

* Updates

* Overview updates

* Nav data

* More nav updates

* Fix

* updates

* Updates + tip test

* Directory test

* refining

* Create restructure w/ k8s

* Single usage page

* Technical Specification

* k8s pages

* typo

* L7 traffic management

* Manage connections

* k8s page fix

* Create page tab corrections

* link to k8s

* intentions

* corrections

* Add-on intention descriptions

* adjustments

* Missing </CodeTabs>

* Diagram improvements

* Final diagram update

* Apply suggestions from code review





* diagram name fix

* Fixes

* Updates to index.mdx

* Tech specs page corrections

* Tech specs page rename

* update link to tech specs

* K8s - new pages + tech specs

* k8s - manage peering connections

* k8s L7 traffic management

* Separated establish connection pages

* Directory fixes

* Usage clean up

* k8s docs edits

* Updated nav data

* CodeBlock Component fix

* filename

* CodeBlockConfig removal

* Redirects

* Update k8s filenames

* Reshuffle k8s tech specs for clarity, fmt yaml files

* Update general cluster peering docs, reorder CLI > API > UI, cross link to kubernetes

* Fix config rendering in k8s usage docs, cross link to general usage from k8s docs

* fix legacy link

* update k8s docs

* fix nested list rendering

* redirect fix

* page error

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Co-authored-by: Jeff Boruszak <104028618+boruszak@users.noreply.github.com>
Co-authored-by: trujillo-adam <47586768+trujillo-adam@users.noreply.github.com>
Co-authored-by: Tu Nguyen <im2nguyen@users.noreply.github.com>
Co-authored-by: David Yu <dyu@hashicorp.com>
Co-authored-by: Tu Nguyen <im2nguyen@gmail.com>