feat(*): converting to standalone components

[kdinev]

Closes #12698

NOTE for reviewers: Go over the *.modules.ts and **/public_api.ts files. The rest should be OK, but I want to make sure the public API is in tact and reflects what should be exported. I'm now exporting less items as public API, as some classes/directives/component should have never been visible. The rest of the changes include rename (for misspelled directives) and deletion of unused/obsolete code.

All of the tests have been transitioned to standalone as well.

Additional information (check all that apply):

• Bug fix
• New functionality
• Documentation
• Demos
• CI/CD

Checklist:

• All relevant tags have been applied to this PR
• This PR includes unit tests covering all the new code (test guidelines)
• This PR includes API docs for newly added methods/properties (api docs guidelines)
• This PR includes feature/README.MD updates for the feature docs
• This PR includes general feature table updates in the root README.MD
• This PR includes CHANGELOG.MD updates for newly added functionality
• This PR contains breaking changes
• This PR includes ng update migrations for the breaking changes (migrations guidelines)
• This PR includes behavioral changes and the feature specification has been updated with them