[META] Prepare Logstash Central Management for new platform

[jen-huang]

This ticket outlines the necessary work to migrate Logstash Central Management to the new platform.

Potential blockers

• ui/management breadcrumbs dependencies
• FeatureCatalogueRegistry dependency

Steps necessary for migration

Client Side

• Convert all code to Typescript
• Remove all Angular UI/Router - most of this app is already in React, but there are still some bootstrapping Angular code: pipeline edit route, pipeline upgrade route
• Create the legacy shim for your NP-style plugin shape
• Move all imports from ui/* to your frontend Legacy shim
• More steps here: https://github.com/elastic/kibana/blob/master/src/core/MIGRATION.md#browser-side-plan-of-action

Server Side

• Move all server.plugins.* calls to your backend Legacy shim
• More steps here: https://github.com/elastic/kibana/blob/master/src/core/MIGRATION.md#server-side-plan-of-action

[jen-huang]

Closing as Logstash Pipelines has been migrated.