Pinned Watchdog version leads to problems when updating

[Witoso]

In the published package on the npm, we pin a specific version of Watchdog which leads to problems when someone is using a different version of the editor or wants to update.

package.json on npm:

React on the other hand specifies Watchdog as a peer dependency: .

Not sure what's the best approach to solve this but it's a major issue for some integrators.

[Reinmar]

We also planned to expose Watchdog on the Editor class to completely avoid this additional dependency. 

Some internal notes where we discussed this:

• Update (13.04.2023):
  • 😂 And the above didn’t work: ckeditor/ckeditor5#13852
  • Two options for now:
    • Add ckeditor5-watchdog to the “Framework” layer and make the base Editor expose these
      • Simpler option
      • Risk: circular dependency on types between the editor and watchdog interfaces
      • This time let’s also update the integrations to verify that it all works together
    • Merge the code from ckeditor5-watchdog to ckeditor5-core, but keep ckeditor5-watchdog as a re-export for backwards compat
      • It would make core the dep of watchdog pkg (it has no deps now)

[pomek]

Scope

• We agreed to define core, engine, utils, and watchdog packages as peer dependencies.
  • They all are needed when an integrator installs the <CKEditor> component and tries to build a custom app.
  • Example: tsc needs to resolve import type { GetEventInfo } from '@ckeditor/ckeditor5-utils';, so the utils package must be installed too.
  • We require at least version 37 or higher (>=37.0.0). 37 is the first number that offers typings.
• It's a breaking change.
• Update the Angular guide. We should mention that peer dependencies should be installed in the same version like the editor build that integrator wants to use.