Air fryer meatballs with cherry tomato sauce

Name: Air fryer meatballs with cherry tomato sauce
Ingredients: 80g/2¾oz breadcrumbs; 2 tbsp milk; 1 medium free-range egg; 500g/1lb 2oz beef mince; 2 tbsp finely chopped fresh parsley; 2 tbsp finely chopped fresh basil; 100g/3½oz feta; 2 garlic cloves, peeled and cut in half; 400g/14oz cherry tomatoes, cut in half lengthways; 1 medium shallot, finely chopped (approx. 50g/1¾oz); 1 tbsp olive oil; 1 tbsp balsamic vinegar; salt and freshly ground black pepper; 400g/14oz dried spaghetti; 2 tbsp butter; 1 tbsp roughly chopped fresh parsley; 1 tbsp roughly chopped fresh basil; 50g/1¾oz feta, crumbled