healthv2: change count to be the total update count.

[tommyp1ckles]

Previously, this was the number of updates in this state level which was reset after a transition.
This would be more intuitive and useful if its just a counter of total updates since the reporter was created.

As well, we'll now store a "time in state level" timestamp which is how long it's been in the current state.

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Fixes: #issue-number

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