Add Docker Hub README and description sync to workflow

[Copilot]

Changes

This PR adds automated syncing of the README.md and repository description to Docker Hub, ensuring both the full description and short description stay up-to-date whenever Docker images are published.

Implementation

Added a new step to the publish job in .github/workflows/docker.yml that uses the peter-evans/dockerhub-description@v3 action. This step:

• Runs after the "Build and push image" step
• Only executes when publishing to Docker Hub (on push to main branch)
• Uses existing DOCKERHUB_USERNAME and DOCKERHUB_TOKEN secrets
• Syncs the ./README.md file to the Docker Hub repository's full description
• Syncs the GitHub repository description to Docker Hub's short description field
• Uses dynamic repository reference with ${{ secrets.DOCKERHUB_USERNAME }}/${{ env.IMAGE_NAME }}

Benefits

• Eliminates manual README and description updates on Docker Hub
• Ensures consistency between the GitHub repository and Docker Hub for both full and short descriptions
• Runs automatically as part of the existing Docker publish workflow

Fixes the issue where Docker Hub descriptions could become outdated when README or repository description changes are made.

- name: Update Docker Hub description + short desc
  uses: peter-evans/dockerhub-description@v3
  with:
    username: ${{ secrets.DOCKERHUB_USERNAME }}
    password: ${{ secrets.DOCKERHUB_TOKEN }}
    repository: ${{ secrets.DOCKERHUB_USERNAME }}/${{ env.IMAGE_NAME }}
    readme-filepath: ./README.md
    short-description: ${{ github.event.repository.description || '' }}

Fixes #9

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Chore: Update docker.yml workflow</issue_title>
<issue_description>Add to the Docker workflow the following so that the README stays in sync on Docker Hub.

  - name: Update Docker Hub description from README.md
    uses: peter-evans/dockerhub-description@v3
    with:
      username: ${{ secrets.DOCKERHUB_USERNAME }}
      password: ${{ secrets.DOCKERHUB_TOKEN }}
      repository: nickytonline/dev-to-mcp
      readme-filepath: ./README.md
```</issue_description>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

Fixes #9

---

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[Copilot]

Pull Request Overview

Adds a CI step to automatically sync the repository README to Docker Hub after publishing images, keeping the Docker Hub description up-to-date.

• Adds peter-evans/dockerhub-description@v3 to the publish workflow
• Uses Docker Hub credentials from repository secrets and README.md as the source

[nickytonline]

@copilot also sync the description, short-description: ${{ github.event.repository.description || '' }}, i.e.

- name: Update Docker Hub description + short desc
  uses: peter-evans/dockerhub-description@v3
  with:
    username: ${{ secrets.DOCKERHUB_USERNAME }}
    password: ${{ secrets.DOCKERHUB_TOKEN }} # this can be a Docker Hub access token
    repository: ${{ secrets.DOCKERHUB_USERNAME }}/${{ env.IMAGE_NAME }}
    readme-filepath: ./README.md
    short-description: ${{ github.event.repository.description || '' }}

[Copilot]

@copilot also sync the description, short-description: ${{ github.event.repository.description || '' }}, i.e.

...

Added the short-description parameter to sync the GitHub repository description to Docker Hub. The step name has also been updated to reflect both syncs. Changes in commit 4086e13.