LONDON — The British capital’s social circuit is set to get busier with the Royal Academy of Arts’ 258th summer exhibition preview party on June 10. This year’s event will be cochaired by leading names across film, music, fashion and contemporary art, including sitarist and composer Anoushka Shankar; British actor Archie Madekwe; Eva Langret, Frieze’s director of the Europe, Middle East and Africa region; royal academician and champion of bold fashion looks Grayson Perry, and Laura Weir, chief executive officer of the British Fashion Council . A London summer fixture, the RA’s summer exhibition preview party gives ticketed guests, who would pay 575 pounds or 850 pounds depending on the experience package, early access to buy works at the world’s longest-running contemporary art show, which has taken place annually since 1769.…