[AO] - Add the flapping alert annotations to the history chart for Log threshold Alert details page

[fkanout]

🗒️ Summary

Part of #150854
Add the flapping alert annotations to the history chart.

✅ AC

TBD

[elasticmachine]

Pinging @elastic/actionable-observability (Team: Actionable Observability)

[maryam-saeidi]

Regarding flapping, I suggest: (not necessarily for v8.8.0)

1. We add all the alerts that contribute to flapping on the alert chart
2. Consider the first alert that contributed to flapping as the start of flapping.

I showed this information in the following image on the top chart. (The bottom charts are just some ideas)

cc @maciejforcone @katrin-freihofner

[fkanout]

Outcomes alert flapping meeting:

• See if we can link the current active alert and the flapping ones (when the alert started flapping). I know we don't create docs when the alert is flapping.
• IF YES: Show the flapped alerts in the main chart as annotations.
• If the rule param changes, if there are any rule conditions changes (rule logs/ API) e.g. Threshold
  cc @XavierM

[maryam-saeidi]

Update after discussion with Xavier:

Currently, we don't have a way to get the rule's history. ResponseOps has a plan for it but probably not for v8.9