dhi: refresh how-to use (#24629)

<!--Delete sections as needed -->

## Description

- Merged the use in k8 topic into the general use topic. 
- Removed the generic dhi differences table and just xref'd to the
migrations topic that also has it.
- Simplified the pull & run section down to just explaining the
different registries.
- Added how to use els variants and removed that standalone topic.
- Replaced dev multi-stage example with an xref to the migration topics
- Added DD auth for k8 example for local dev

## Related issues or tickets

ENGDOCS-3222
ENGDOCS-3226
#24616 as it may cause conflicts.

## Reviews

<!-- Notes for reviewers here -->
<!-- List applicable reviews (optionally @tag reviewers) -->

- [ ] Editorial review

---------

Signed-off-by: Craig Osterhout <craig.osterhout@docker.com>

Author: craig-osterhout

content/manuals/dhi/get-started.md

@@ -74,7 +74,6 @@ a simple Python command just like you would with any other Docker image:
 To dive deeper into using images, see:
 
 - [Use a Docker Hardened Image](./how-to/use.md) for general usage
-- [Use in Kubernetes](./how-to/k8s.md) for Kubernetes deployments
 - [Use a Helm chart](./how-to/helm.md) for deploying with Helm
 
 ## Step 3: Compare with other images

content/manuals/dhi/how-to/_index.md

@@ -33,18 +33,10 @@ params:
       description: Learn how to pull, run, and reference Docker Hardened Images in Dockerfiles, CI pipelines, and standard development workflows.
       icon: play_arrow
       link: /dhi/how-to/use/
-    - title: Use a Docker Hardened Image in Kubernetes
-      description: Learn how to use Docker Hardened Images in Kubernetes deployments.
-      icon: play_arrow
-      link: /dhi/how-to/k8s/
     - title: Use a Docker Hardened Image chart
       description: Learn how to use a Docker Hardened Image chart.
       icon: leaderboard
       link: /dhi/how-to/helm/
-    - title: Use Extended Lifecycle Support for Docker Hardened Images
-      description: Learn how to use Extended Lifecycle Support with Docker Hardened Images.
-      icon: update
-      link: /dhi/how-to/els/
     - title: Manage Docker Hardened Images and charts
       description: Learn how to manage your mirrored and customized Docker Hardened Images in your organization.
       icon: reorder

content/manuals/dhi/how-to/els.md

@@ -1,7 +1,7 @@
 ---
 title: Use Hardened System Packages
 linkTitle: Use hardened packages
-weight: 30
+weight: 32
 keywords: hardened images, DHI, hardened packages, packages, alpine
 description: Learn how to use and verify Docker's hardened system packages in your images.
 ---

content/manuals/dhi/how-to/hardened-packages.md

@@ -3,7 +3,7 @@ title: Use a Docker Hardened Image chart
 linktitle: Use a Helm chart
 description: Learn how to use a Docker Hardened Image chart.
 keywords: use hardened image, helm, k8s, kubernetes, dhi chart, chart
-weight: 32
+weight: 31
 ---
 
 Docker Hardened Image (DHI) charts are Docker-provided [Helm

content/manuals/dhi/how-to/helm.md

@@ -154,9 +154,8 @@ repository.
 
 > [!NOTE]
 >
-> If you only want to stop mirroring ELS versions, you can clear the ELS
-> option in the mirrored repository's **Settings** tab. For more details, see
-> [Disable ELS for a repository](./els.md#disable-els-for-a-repository).
+> If you only want to stop mirroring ELS versions, clear the **Mirror
+> end-of-life images** option in the mirrored repository's **Settings** tab.
 
  To stop mirroring a repository:
 

content/manuals/dhi/how-to/k8s.md

@@ -231,7 +231,6 @@ image from your organization namespace on Docker Hub.
 To dive deeper into using images, see:
 
 - [Use a Docker Hardened Image](use.md) for general usage
-- [Use in Kubernetes](k8s.md) for Kubernetes deployments
 - [Use a Helm chart](helm.md) for deploying with Helm
 
 ## Step 5: Remove customization and stop mirroring