Leetcode 1783. Grand Slam Titles

Given a list of tournament win records (player, tournament, year), determine which players have claimed all four Grand Slam titles (the Australian Open, French Open, Wimbledon, and US Open) by grouping wins and checking set coverage—either within a single calendar year (calendar-year grand slam) or across their career (career grand slam). The core challenge is efficient aggregation and set membership checks (grouping by player and optionally by year), handling duplicates and large input sizes.