// Package achievements provides a complete achievement system for EQ2Emulator servers.
//
// Features:
//   - Achievement definitions with requirements and rewards
//   - Thread-safe master achievement list for server-wide management
//   - Player-specific achievement tracking and progress
//   - Database operations with both SQLite and MySQL support
//
// Basic Usage:
//
//	// Create database connection
//	db, _ := database.NewSQLite("world.db")
//	// db, _ := database.NewMySQL("user:pass@tcp(host:port)/dbname")
//
//	// Create new achievement
//	achievement := achievements.New(db)
//	achievement.AchievementID = 1001
//	achievement.Title = "Monster Slayer"
//	achievement.Category = "Combat"
//	achievement.PointValue = 50
//
//	// Add requirements and rewards
//	achievement.AddRequirement("kill_monsters", 100)
//	achievement.AddReward("experience:5000")
//
//	// Save to database (insert or update automatically)
//	achievement.Save()
//
//	// Load achievement by ID
//	loaded, _ := achievements.Load(db, 1001)
//
//	// Update and save
//	loaded.Title = "Master Monster Slayer"
//	loaded.Save()
//
//	// Delete achievement
//	loaded.Delete()
//
// Master List Management:
//
//	// Create master list for server-wide achievement management
//	masterList := achievements.NewMasterList()
//
//	// Load all achievements from database
//	allAchievements, _ := achievements.LoadAll(db)
//	for _, ach := range allAchievements {
//		masterList.AddAchievement(ach.ToLegacy())
//	}
//
//	// Get achievements by category
//	combatAchievements := masterList.GetAchievementsByCategory("Combat")
//
// Player Progress Management:
//
//	// Player achievement management
//	playerMgr := achievements.NewPlayerManager()
//	achievements.LoadPlayerAchievements(db, playerID, playerMgr.Achievements)
//	achievements.LoadPlayerAchievementUpdates(db, playerID, playerMgr.Updates)
package achievements