message: docs: update stability index for core-*
diff: @@ -108,50 +108,33 @@ Stability: `1`. Mainly intended for internal use.
  ### `core` [GitHub](https://github.com/backstage/backstage/tree/master/packages/core/)
  -#### Section: React Components
  +The `@backstage/core` and `@backstage/core-api` packages are being phased out
  +and replaced by other `@backstage/core-*` packages. They are still in use but
  +will not receive any breaking changes.
  -All of the React components exported from `src/components/` and `src/layout/`
  -
  -Stability: `1`. These components have not received a proper review of the API,
  -but we also want to ensure stability.
  -
  -#### Section: Plugin API
  -
  -The parts of the core API that are used by plugins, and the way plugins expose
  -functionality to apps and other plugins. Includes for example `createPlugin`,
  -`createRouteRef`, `createApiRef`.
  +### `core-api` [GitHub](https://github.com/backstage/backstage/tree/master/packages/core-api/)
  -Stability: `2`. There are planned breaking changes around the way that plugins
  -expose features and do routing. We still commit to keeping a short deprecation
  -period so that plugins outside of the main repo have time to migrate.
  +Stability: See `@backstage/core` above
  -#### Section: App API
  +### `core-app-api` [GitHub](https://github.com/backstage/backstage/tree/master/packages/core-app-api/)
  The APIs used exclusively in the app, such as `createApp` and the system icons.
  -Stability: `2`
  +Stability: `2`.
  -#### Section: Utility API Definitions
  +### `core-components` [GitHub](https://github.com/backstage/backstage/tree/master/packages/core-components/)
  -The type declarations of the core Utility APIs.
  +A collection of React components for use in Backstage plugins and apps.
  +Previously exported by `@backstage/core`.
  -Stability: `2`. Changes to the Utility API type declarations need time to
  -propagate.
  -
  -#### Section: Utility API Implementations
  -
  -The interfaces and default implementations for various Utility APIs, such as
  -ErrorApi, IdentityApi, the auth APIs, etc.
  -
  -Stability: `1`. Most changes to the core utility APIs will not lead to
  -widespread breaking changes since most apps rely on the default implementations.
  +Stability: `1`. These components have not received a proper review of the API,
  +but we also want to ensure stability.
  -### `core-api` [GitHub](https://github.com/backstage/backstage/tree/master/packages/core-api/)
  +### `core-plugin-api` [GitHub](https://github.com/backstage/backstage/tree/master/packages/core-plugin-api/)
  -The non-visual parts of @backstage/core. Everything in this packages is
  -re-exported from @backstage/core, and this package should not be used directly.
  +The core API used to build Backstage plugins and apps.
  -Stability: See @backstage/core
  +Stability: `2`.
  ### `cost-insights` [GitHub](https://github.com/backstage/backstage/tree/master/plugins/cost-insights)
  