eventCount property
How many, and on which channels — {platform: 3, print: 1}. The badge on
the flow's arrow, and the part of the digest that survives filtering.
Null — not zero, not {} — on a transition where nothing happened, which
is most of them: four keys saying "none" on every step of a fifty-step
run is noise an agent pays for. hasEvents is the question worth asking.
Implementation
final int? eventCount;