Support counter style graph for extra events

magic-trace will soon support you sampling additional events such as cache-misses. However it would be nice if there was an option to not just see them as arrows, but even perhaps have a graph (like counter tracks in perfetto) which would try to approximate the frequency of the event over time based on the samples. Depending on what one is looking for, this might be a better UX experience than an excessive amount of arrows for high frequency events.

Start by tracing how additional sampled events are currently represented as arrows in magic-trace and compare the desired behavior with Perfetto counter tracks. The work is complete when high-frequency events can be shown as a time-based graph that approximates event frequency from samples and provides a better alternative to excessive arrows.

Written by the indexing model from the issue text.