viz options should validate intervals based on data

[matthewcornell]

Per this slack thread with @nickreich :

right now, the viz config page accepted me adding “80” as an option for the intervals array. But should it allow me to do that, or should those inputs be somehow pre-verified as ones I can select? This may not be essential to update/fix, but was just curious.
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I guess my question is whether or not there is (or should be) any validation about which intervals are computable for a given project. Maybe this is too far in the weeds, but say someone put in “55”. That interval can’t be computed from the given quantiles. If they put in “80" it could be. What would happen it a user specified either or both of those intervals?