Reorganize images into a structured hierarchy that mirrors the documentation structure

[sgort]

To Do

• Scan all markdown/mdx files in the docs folder
• Identify which sidebar section each file belongs to (get-started, documentation, security)
• Organize images into structured folders matching the docs structure
• Update all image references in the markdown files

Expected Result

static/
  img/
    favicon.png
    operaton-logo.svg
    get-started/
      installation/
        screenshot-1.png
        screenshot-2.png
      quickstart/
        diagram.png
    documentation/
      user-guide/
        task-management.png
      api/
        endpoint-example.png
    security/
      authentication-flow.png
      ssl-setup.png
    shared/
      # Images not belonging to a specific section

Optional

• Consider running an optimization pass (ie https://github.com/imagemin/imagemin)
• For better performance, convert images to WebP

[sgort]

I left the optional optimization pass and/or convert to WebP for now. Might do that later and will create an issue for that.