Determine first wizard step

[grotlue]

First Step:

• If illuminate is not up to date -> https://github.com/Graylog2/graylog-plugin-enterprise/issues/8873
• If illuminate is up to date
  • and category/subcategory are set
    • and category/subcategory are valid for Illuminate -> https://github.com/Graylog2/graylog-plugin-enterprise/issues/8872
    • and category/subcategory are not valid for Illuminate -> https://github.com/Graylog2/graylog2-server/issues/20683
  • and category/subcategory are not set -> https://github.com/Graylog2/graylog2-server/issues/20564

Dependencies:

• Checking illuminate validity depends on https://github.com/Graylog2/graylog2-server/issues/20684

APIs:

• For checking if Illuminate is up to date: http://localhost:8080/api/api-browser/global/index.html#!/Plugins/Illuminate/getStatus_get_3