ax(database): replace prose comment with usage example on GetAllMinerStats

Co-Authored-By: Charon <charon@lethean.io>

pkg/database/hashrate.go

@@ -185,7 +185,9 @@ func GetHashrateStats(minerName string) (*HashrateStats, error) {
 	return &stats, nil
 }
 
-// GetAllMinerStats retrieves stats for all miners
+// GetAllMinerStats returns aggregated performance data for every known miner.
+// allStats, err := database.GetAllMinerStats()
+// for _, stats := range allStats { fmt.Println(stats.MinerName, stats.AverageRate) }
 func GetAllMinerStats() ([]HashrateStats, error) {
 	databaseMutex.RLock()
 	defer databaseMutex.RUnlock()