By Andy Bruce LONDON (Reuters) – British retail sales jumped unexpectedly in April as shoppers loaded up on alcohol and tobacco, likely a blip in an otherwise bleak trend that has driven consumer confidence to all-time lows amid a worsening cost-of-living crunch. Retail sales volumes rose 1.4% month on month after a 1.2% drop in March, the Office for National Statistics said. Economists polled by Reuters had expected a 0.2% monthly fall. The wider picture remains disconcerting. Retail sales in the three months to April fell 0.3%, after a 0.7% drop in March. Compared with a year ago, sales volu…