[Alerting] [o11y] Determine how to represent collected metrics

[chrisronline]

Relates to #98902 (comment)

Once we determine the set of metrics that are valuable (see #100675), we want to take a small amount of time to think through how an end user might leverage these metrics. This will most likely be some sort of dashboard, but it will be helpful to know as many specifics as possible to ensure the data is shaped appropriately.

For example, if we envision users will only (at least for the short term) be interested in the top n slowest of something, perhaps we can modify data collection to only collect those particular data points (as our current monitoring metrics collect rolling averages so it seems possible to do a little logic before shipping data to only ship top n slowest, or something along those lines)

[elasticmachine]

Pinging @elastic/kibana-alerting-services (Team:Alerting Services)

[chrisronline]

Closing as the new proposal is taking down a different path in the short term