Generate summary using AI (frontend)

[tusmester]

As an editor I want a possibility to generate a summary into a text field from another, long text field.

• a button/icon on one field to generate a summary from another field
• not forced, only generate a summary if a user presses a button
• configured in the CTD (see related issue), see available CTD properties there
• tooltip on the button: "Generate a short summary from [field]"
• the target can be either a shorttext or a longtext field