Core plugins support (server side)

[epixa]

The server-side plugin service will handle loading plugin details from the static manifest (kibana.json), sorting the plugins based on their dependency graphs, initializing the various server-side plugins, and wiring their lifecycle into the lifecycle of the plugin service itself (start/stop). It'll also configure the HTTP service so that client-side plugin bundles can be served to the browser and ensure the ordered array of plugin names is passed to the browser.

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details are probably going to change here

Plugins in the new platform will be different from "legacy" plugins in many ways. The first of those ways is that they define static metadata in a kibana.json file within a directory:

foo/kibana.json (comments allowed)

{
  // required - id for your plugin
  "id": "foo",

  // required - the version of your plugin
  "version": "x.y.z",

  // optional - the version of Kibana your plugin is compatible with, defaults to "version"
  "kibanaVersion": "x.y.z",

  // optional - the other plugins that must be installed and enabled for this plugin to work.
  "requiredPlugins": ["..."],
  
  // optional - when true the `public/ui_plugin.js` file will be included in the new-platform bundle
  "ui": true
}

Note: The browser-side plugin is support is going to be handled separately in #18874.

---

Blocked by:

• Expose core config schema validation system as @kbn/config-schema package (PR, merged)
• Add Kibana bootstrap step to generate types exposed by the core and its plugins (PR, merged)
• Implement new platform plugin discovery. (PR, merged)
• Introduce support for the server-side new platform plugins. (PR, merged)
• Move legacy src/core_plugins to src/legacy/core_plugins. (PR, merged)
• Implement first core server-side only plugin. (PR, merged)

[azasypkin]

Since #25473 has just landed we can close this issue and open separate more targeted issues as we go.