[Feature] Show Threshold (Lines) on Dashboard instead of (just) average

[davidh2k]

Pre-work

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Description

I'd like to see a Threshold marker line in the Dashboard, to spot (or show the amount of) speedtests that we're below the threshold rather than the average which, for me, does not really net any benefit since it can be pretty bland most of the time.

A Threshold line however would also give me an easy to make screenshot to throw at my ISP to specifically show how often my line falls beneath the regulatory minimum.

[davidh2k]

I know that there is the option in the results to filter for Threshold events, but I think having it also reflect somewhat in the Dashboard would be beneficial.