I cannot speak to the affect it may have on Citizenship; however if you both did not show at the hearing then it is likely the Restraining Order was vacated. If your partner did show at the hearing and you did not, then it is likely it was continued for a period of one year. I would recommend you go to the Court and obtain a copy of the vacated Order to confirm.
This response is for informational purposes only and not intended to be legal advice; nor is this answer intended to create an attorney/client relationship. Legal advice and an attorney/client relationship can only be rendered after a full in person consultation has been conducted with an attorney wherein all necessary facts and circumstances are disclosed. To the extent additional or different facts exist, the within response may be different.
If neither of you showed up at the extension hearing, the order would have expired on its own and no further action is required on your part. Record of the short-term initial order, however, does appear on the state domestic violence registry. A restraining order is civil, not criminal, in nature and should not have a negative impact on your status as a lawful permanent resident nor prevent you from becoming a citizen.