Thanks for your question.

To provide you some background information, check out the following:

https://www.bugoutservice.com/pest-info/ants/carpenter-ant/ - :~:text=The life cycle of carpenter,months, depending on environmental conditions.

https://www.orkin.com/pests/ants/carpenter-ants/life-cycle-of-carpenter-ants

There is no quick way to get rid of these ants. My guess is there is a nest somewhere within the outside wall near your deck door.. Possibly this was started in 2023 and with warmer weather, the ants are now starting to be active once again. This is really something for which you will need the services of a professional exterminator. There is a queen ant within this nest who is continually laying eggs. As long as she exists, you will have ants appearing. I have sometimes seen that it may take two or three visits by an exterminator before the problem is solved. Carpenter ants are attracted to moist locations. Keep this in mind as you try to locate where this nest is.

As Extension Master Gardeners of the University of Minnesota, we cannot endorse any specific commercial venture. However, the following site may get you started:

https://www.angi.com/companylist/us/mn/ramsey/pest-control.htm

The concern you have for your cat is quite valid. This is an issue that would best be taken up by an exterminator.

Good luck. Thanks for consulting us.