In "Lamb to the Slaughter," what does Mary Maloney do for her husband coming home?

Everything! It really is quite sickening the way that Mary
Maloney panders to her husbands every whim. Just consider the first paragraph of the
story and see how it presents her as a wife who is completely devoted to her
husband:

The
room was warm and clean, the curtains drawn, the two table lamps alight--hers and the
one by the empty chair opposite. On the sideboard behind her, two tall glassess, soda
water, whisky. Fresh ice cubes in the Thermos bucket.

Mary
Maloney was waiting for her husband to come home from
work.

Note how everything is
completely ready for her husband's arrival. She has clearly worked hard to do this, and
we can infer from her attitude towards her husband that she does this every single day
for him as well. I know it was just Valentine's Day yesterday, but please: this is
rather exaggerated. Of course, you need to be aware of what Dahl is doing through this.
He is clearly setting up her character as a devoted wife, which makes the situational
irony of what happens later in the story all the more acute.