[Meta] Fleet Server Phase 2

[ruflin]

Goal of this phase is to bring Fleet-Server to beta stage. This is a meta tracking issue.

• Use Elasticsearch system indices (@scunningham)
  • Elasticsearch change: Introduce system index types including external elasticsearch#68919
  • Fleet server system indices Manage fleet server indices as system indices in the Elastic Stack #135 (Jay)
  • Switch fleet-server over to system indices
• Elastic Agent with Fleet Server enrolls itself Elastic Agent with Fleet Server enrolls itself #55
• User permission definition Define permissions user for fleet-server needs #60 (@scunningham )
• Support TLS Handling of TLS #90 (@blakerouse )
• Metrics of Fleet Server Collect and expose metrics from fleet-server #99 (@scunningham )
• Handle existing actions like upgrade properly ( @blakerouse )
• Pull out saved object code ( @aleksmaus )
• More granular permissions [Discuss] Indexing permissions as part of the Elastic Agent policy #101 (@aleksmaus )
• Implement support for API Key metadata. ES reference: Metadata for API keys elasticsearch#48182 Implement support for API Key metadata #193 (@aleksmaus )
• Add support for service tokens for fleet-server (@blakerouse )
• Validate Elasticsearch version for compatibility Validate Elasticsearch version for compatibility #167 (@blakerouse )
• Validate fleet-server compatibility in Elastic Agent https://github.com/elastic/beats/issues/24720 (@blakerouse )

Bugs

• .fleet-actions index not found .fleet-actions index not found #246

CI

• End to end tests exists for Elastic Agent startup, agent enrollment and receiving policy. [Fleet] Infra work / new test creation, for coming Fleet Server component  e2e-testing#438 (@blakerouse )
• Scale testing setup [Meta] Fleet Server Scale Testing #95 (@aleksmaus )
  • Basic APM Server testing in Cloud container (@simitt)
  • Basic fleet-server testing in Cloud container (@scunningham )

Docs (@ph )

[ruflin]

I checked off e2e tests as some initial work for elastic/e2e-testing#438 was merged. More is needed but tracked in elastic/e2e-testing#438

[ruflin]

Closing this issue as all related tasks have been completed. The testing is ongoing and will continue.