Returns level when support lists it, otherwise the nearest supported level on the effort scale,
preferring the higher neighbour (an unsupported minimal becomes low, not off). An unsupported
'auto' resolves to defaultLevel, then to the first supported level. Returns level unchanged
when nothing suitable is supported.
Returns
levelwhensupportlists it, otherwise the nearest supported level on the effort scale, preferring the higher neighbour (an unsupportedminimalbecomeslow, notoff). An unsupported'auto'resolves todefaultLevel, then to the first supported level. Returnslevelunchanged when nothing suitable is supported.