Wizard Step: Setup Routing

[grotlue]

• Shows a select with all existing streams
  • default option: All messages (Default Stream)
  • The user can select any other existing stream
• if pipelines are attached to the selected stream -> warn the user and ask if they want to select another
• Shows a button "Create new Stream", clicking leads to https://github.com/Graylog2/graylog2-server/issues/20569
• "Finish and Start Input" will lead to https://github.com/Graylog2/graylog2-server/issues/20567

[grotlue]

APIs:

• http://localhost:8080/api/api-browser/global/index.html#!/Streams/get_get_0 to list all streams