Eu trouxe garfos e colheres para a sobremesa de domingo.

Trouxe is the first-person singular pretérito perfeito of trazer (“to bring”). You use it for a single, completed action in the past.
If you wanted to describe a habitual past action, you’d use trazia (pretérito imperfeito). The conditional (“would bring”) is traria.

No, Portuguese is a pro-drop language. The subject pronoun eu can be omitted because the verb ending already indicates the person.
So Trouxe garfos e colheres… is perfectly natural. You’d include eu only for emphasis or clarity.

Trazer means “to bring” toward the speaker or where the speaker is/will be.
Levar means “to take” away from the speaker.
Use trouxe if you (the speaker) are the reference point receiving or using the forks and spoons.

Without articles, garfos e colheres is indefinite: “some forks and spoons.”
If you meant “the forks and the spoons” (specific utensils already known), you’d say os garfos e as colheres.

A sobremesa is definite here because it refers to a specific course—the dessert. Both speaker and listener know which course is meant.
By contrast, garfos e colheres just means “some utensils,” so no article is needed for an indefinite reference.

In Portuguese, most nouns need an article when they’re definite: hence a sobremesa.
The phrase de domingo indicates association or possession (“Sunday’s dessert”).

Yes, do domingo is the contraction of de + o domingo.
Sobremesa de domingo is a neutral label (“Sunday dessert” as a category).
Sobremesa do domingo (“the dessert of the Sunday”) feels more specific—referring to that particular Sunday’s dessert.

Para a sobremesa de domingo means “for Sunday’s dessert” (dessert belonging to Sunday).
If you said para a sobremesa no domingo, you’d shift to time: “for the dessert on Sunday,” emphasizing when, not whose dessert.