My experience is that veggies need sun. I've disabled my "vegetable garden" by planting apple trees, and it's now so shaded that I grow all my veg in pots up on the terrace.
Alpine strawberries do well in the shade and they give a good crop. Raspberries and hybrid blackberries (like loganberries and tayberries) also give a good enough crop to be worth growing.
But in your case I'd go ornamental, since it's the backdrop to your seating area. No lawn, and open space covered with bark chippings or similar. Then plant a good selection of "shade" plants, trying to give all year round interest, and remember that in spring there'll be more light to it, so you can have a whole raft of spring bulbs, and primroses and other primulas that don't like getting too hot and dry.
It's nice to pay attention to winter stuff so that you have reason to walk down there for a look in the winter. Hamamelis, winter flowering Viburnum, shade tolerant evergreens, things with good coloured stems (eg Cornus, some willows), autumn flowering Cyclamen hederifolium, spring flowering C coum.
Then you could move into winter aconite, snowdrops, small dainty daffodils etc. And Hellebores with long lasting coloured bracts.
For summer a range of perennials, eg Astrantia, Heuchera (also has good leaf colour), Tellima (very shade tolerant), Rogersia.
Arrange it as a sort of circular stage, with very low scattered bulbs in front, shading back to perennials then shrubs.