Instance Types are grouped by actual shape now, so each row/series is one
concrete type. Label them accordingly via a shared instanceTypeSeriesLabel,
used by both the table column and the trend legend so they read identically:
GPU shows "<product> x <cards>", CPU shows "CPU Only · N vCPU · M GB" (the
instance's real size, not the bare "CPU Only" + hover tooltip). The Instances
tab also uses the per-instance cpu/mem totals, so a 3c6g instance of a 1c2g
flavor reads 3c6g instead of 1c2g. flatten carries cpu_milli/memory_mib/
gpu_count from the breakdown dimensions.