[Logs UI][Metrics UI] Reduce `infra` bundle size

[afgomez]

Our bundle limit size is currently at 200KB. We would like to reduce that to increase the page load time. As a challenge we would like to cut that limit in half.

Questions

• What are the outliers in infra.bundle.js?
• Can they be loaded asyncronously?
• Can they be replaced with a light weight alternative?
• Is there any dead weight?

Related: what can we do to reduce the overall footprint of the infra plugin? Even if the entry point is around 200K, some of the other chunks are well above that.

[elasticmachine]

Pinging @elastic/logs-metrics-ui (Team:logs-metrics-ui)

[afgomez]

I have noticed some things in our bundle:

Potentially unnecessary modules

• Inside node_modules there are two big boxes: URL and mustache. We can see where they are being used and potentially replace them with native alternatives or remove them completely.

Alerting components

• Inside public/alerting and common/alerting there are modules for log_threshold and metric_threshold. These can potentially be moved so the log modules are loaded only in logs, and the metrics only in metrics.