Profile card customization, lobby stats & homepage improvements
- Profile Card: players can now choose which 2 stats to display on their card (Level, Games, ELO, Best Streak, Accuracy, Wins).
- Profile Card: stats are now consistent everywhere — same dynamic display on profile page, leaderboards, friends list, lobbies, etc.
- Lobby: game answers are now recorded in player stats (accuracy, games played).
- Homepage: added 'My Stats' slide to the profile slider with a quick preview of Level, ELO, Games and Best Streak.
- Homepage: fixed profile slider navigation — all 3 slides (Profile, Stats, Friends) are now properly accessible.
- Stats page: added a shortcut link in the homepage bottom bar for quicker access.
- Performance: stats page queries (multiplayer, lobby, campaign, weekly, ranks, submissions, battlepass) are now cached in session (5 min TTL) to reduce database load.
- Database: optimized player_answers table — stores only player_id, is_correct, difficulty and timestamp.