Add personality traits for ingame characters (player and bots)

See also:

• https://www.simplypsychology.org/big-five-personality.html
• https://www.gesis.org/angebot/studien-planen-und-daten-erheben/items-und-skalen/bfi-10
• https://zis.gesis.org/skala/Rammstedt-Kemper-Klein-Beierlein-Kovaleva-Big-Five-Inventory-(BFI-10)