[nextjs-xmcloud][sitecore-jss-nextjs] Component Library endpoint

[art-alexeyenko]

• This PR follows the Contribution Guide
• Changelog updated
• Upgrade guide entry added

Description / Motivation

Extends api/editing/render endpoint with Component Library functionality - so that a single component can be rendered and experimented with.

The implementation has two main parts:

• REST Component service - retrieves component data for a component with uid, item id and other inputs
• ComponentLibraryLayout component - renders the component, sends out the component:ready event and handles component updates from component:update event.
• A dedicated component-library/render route, exclusive to XMCloud, for component library functionality

Some parts of the logic are prepared to be reused for other frameworks.

Please don't merge until release prep for 22.3 begins.

Testing Details

• Unit Test Added
• Manual Test/Other (Please elaborate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

[stasmaxymov]

PR is missing a part with component update listener

[illiakovalenko]

Great job, Artem!
See my comments/questions below. I assume that internal document is not updated and because of that I have concerns related to the defined contract, or there is a different issue (or I missed some part)