Which player played the least number of seasons with one team and had his number retired with said team?

How about Ray Bourque. He was traded to Colorado late in the 99-2000 season, so he could win the Cup, which the Avalanche did the following season. He only played 14 games in 99-00 and then 1 full season in 00-01. So that's not even a season and a quarter with Colorado and they retired his number.