formatAmount

Format an amount as "N,NNN.NN <shortLabel>" (e.g. "12,345.67 tokens"), or "n/a" for null.

Locale.ROOT pins the thousand-separator to , and the decimal mark to . regardless of the JVM's default locale — the produced string is consumed by the cluster Python parser (parseAmount plus the cluster's format_consumption), and a 12.345,67 from a German JVM would break round-trips.