1. Line a 5- x 3-inch mini-loaf pan with clear or colored plastic wrap, allowing extra wrap to extend over the edges of the pan so that you can seal the top when done. In a medium bowl, combine cream cheese, goat cheese, and milk; mix well. Spread pesto in bottom of plastic wrap-lined pan. Spread half of cheese mixture over pesto.
2. Combine the olives; spread over cheese mixture, pressing down with back of a spoon or spatula. Spoon remaining cheese mixture over olives; spread to an even layer with a spatula. Spoon sun-dried tomatoes evenly over cheese mixture, pressing down with back of a spoon or spatula.
3. Bring edges of plastic wrap up over terrine; seal tightly. Refrigerate at least 4 hours or up to 24 hours to set.
4. To serve, unmold terrine onto a plate or platter; surround with wheat crackers. Terrine can be stored in the refrigerator up to 3 days after making.