feature/issue 923 native import attributes for CSS and JSON (#1215)

* intial draft of import attributes support for CSS and JSON

* all test cases passing

* need patch package

* wcc patches for import attributes and CSSStylesheet shim

* bump min NodeJS version for exp specs

* temp disable ESLint

* develop based import assertion specs

* serve based import attributes specs

* add preIntercept resource plugin lifecycle and refactor PostCSS to use it

* all test cases passing for import attributes support

* refactor built in CSS and JSON intercepting

* demo code

* raw plugin docs and package.json updates

* update latest documentation for custom loaders support in NodeJS

* update custom import docs

* upgrade wcc v0.13.0

* only need Node 18 for github actions

* css imports and raw plugin interop with test cases

* lit renderer import attribute test cases and documentation

* refactor matchers support for raw plugin instead of patching and add test cases

* disable describe.only

* update usage for custom resource plugins to showcase usage of import attributes

* document preIntercept lifecycle and convert Babel to use it

* restore ESLint

* enable debug logging for failing specs

* refactor theme pack specs

* fix linting

* remove CSS and JSON packages from being publishable

* clean up console logs and comments

* rename exp test cases to loadersnaming prefix

* fix command in github actions

* remove plugin-import-css callout from plugin-postcss README

* remove demo code from website

* refine PostCSS plugin intercepting

packages/plugin-import-json/package.json

@@ -1,6 +1,7 @@
 {
   "name": "@greenwood/plugin-import-json",
   "version": "0.30.0-alpha.2",
+  "private": true,
   "description": "A Greenwood plugin to allow you to use ESM (import) syntax to load your JSON.",
   "repository": "https://github.com/ProjectEvergreen/greenwood",
   "homepage": "https://github.com/ProjectEvergreen/greenwood/tree/master/packages/plugin-import-json",