À GUY AND HIS BLUES By Mike Franco Fired Up and Foil-Wrapped: Mike Franco has his trusty Weber at the ready, with bluefish fillets, sweet peppers, onions, and grape tomatoes headed for a delicious date with the grill. So here’s the thing. Don’t pay attention to that Midwestern brother-in-law of yours whose summer visits to your Cape Cod getaway all too often are compounded by his constant commentary touting the superiority of brook trout over our local saltwater gems. Or perh