Hey Judah!
Love that you want to be polite about it. Just vibe it out and trust your gut because your energy will carry the message. People totally get it when you're authentic and confident. Shoot off something that sounds like you and move on with your night. You'll be legendary at boundaries in no time.
Blue-light filter, cheap blackout curtains, and my landlord's noise—ugh. For what it's worth, taking a few minutes to practice this in a calm setting usually helps it stick.