[Meta] [Elastic Synthetics Integration UI] Deprecate Legacy Elastic Synthetics UI and Migrate legacy Elastic Synthetics integrations

[dominiqueclarke]

Deprecates existing UI flows for the Elastic Synthetics Integration, ensuring that the only way to create monitors in the UI is through Uptime or Synthetics, and that existing legacy Elastic Synthetics integration policies are able to be migrated into Uptime monitor saved objects.

• [Elastic Synthetics Integration] Deprecate Legacy Synthetics Integration Add Monitor Flow #137501
• [Synthetics] Migrate legacy Elastic Synthetics Integration integration policies to Synthetics Monitor Management #137494
• [Synthetics] Notify legacy Synthetics integration being deprecated #150287
• [Elastic Synthetics Integration] Deprecate Legacy Elastic Synthetics Integration edit flow #137505
• [Synthetics] Legacy Integration - Disable configuration via Kibana YAML #144856

[elasticmachine]

Pinging @elastic/uptime (Team:uptime)

[andrewvc]

Instead of a migration it might be better to, as a first step, just show a large warning when editing those monitors and to show a warning in the synthetics app if they have active legacy integrations.

Thoughts @drewpost @paulb-elastic @hbharding ?

[paulb-elastic]

@andrewvc had left some comments/questions on sub-issues.

If we don't offer the migration, it does simplify not needing to write and test the migrations, but it’s a poorer experience for those with existing Integrations (which I understand @drewpost was keen to help with).

I like your idea of a phased approach - initially indicating the new way of setting these up without removing the current mechanism (having got through the warning/info). Would there be a way to use that implementation to gauge usage and value of adding a migration?

[paulb-elastic]

#150287 added to meta

[shahzad31]

Meta issue, skipping POST FF