Move core-cli-utils to private/ as a reference implementation (#56922)

Summary:
Pull Request resolved: #56922

Move `react-native/core-cli-utils` from `packages/` to `private/`, stop publishing it to npm, and reframe it as a reference implementation of React Native CLI tooling.

The package has no known external consumers and is only used internally by `private/helloworld/` and `packages/rn-tester/`. Publishing it to npm creates a maintenance surface for a package that serves no external users.

See react-native-community/discussions-and-proposals#1002.

#### Changes

- Move `packages/core-cli-utils/` to `private/core-cli-utils/`.
- Convert all source files to CJS (require/module.exports) with Flow comment syntax (/*:: */), eliminating the runtime Babel dependency.
 - Remove from the JS build pipeline (`scripts/build/config.js`).
 - Remove the defunct `patchCoreCLIUtilsPackageJSON()` runtime patching from both `helloworld/cli.js` and `rn-tester/cli.js`, and delete both `monorepo.js` files that contained it.
  - Add as `devDependency` to `rn-tester` and `helloworld`.
  - Skip `"*"` version deps in `_prepareHelloWorld()` so they aren't rewritten to the Verdaccio-published version.
  - Remove redundant desktop import ignore entry (`private/**` already covers it).
  - Rewrite README as reference implementation documentation.

Changelog:
[General][Breaking] - The `react-native/core-cli-utils` package is no longer published. It remains available in the React Native repo as a reference implementation.

Reviewed By: cortinico

Differential Revision: D105959855

fbshipit-source-id: 42e439a45273bdeca76029eff306cdf2451308e2

Author: huntie

packages/core-cli-utils/README.md

@@ -18,7 +18,7 @@ import type {Command} from '@react-native-community/cli-types';
 // depending on and injecting:
 // - @react-native-community/cli-platform-android
 // - @react-native-community/cli-platform-ios
-// - @react-native/community-cli-plugin (via the @react-native/core-cli-utils package)
+// - @react-native/community-cli-plugin
 // - codegen command should be inhoused into @react-native-community/cli
 //
 // This is a temporary workaround.

packages/core-cli-utils/package.json

@@ -12,30 +12,11 @@
 import {Command} from 'commander';
 */
 
-// eslint-disable-next-line @react-native/monorepo/sort-imports
-const {patchCoreCLIUtilsPackageJSON} = require('./scripts/monorepo');
-
-function injectCoreCLIUtilsRuntimePatch() {
-  patchCoreCLIUtilsPackageJSON(true);
-  const cleared = {
-    status: false,
-  };
-  ['exit', 'SIGUSR1', 'SIGUSR2', 'uncaughtException'].forEach(event => {
-    if (cleared.status) {
-      return;
-    }
-    patchCoreCLIUtilsPackageJSON(false);
-    cleared.status = true;
-  });
-}
-
 if (process.env.BUILD_EXCLUDE_BABEL_REGISTER == null) {
   // $FlowFixMe[cannot-resolve-module]
   require('../../scripts/shared/babelRegister').registerForMonorepo();
 }
 
-injectCoreCLIUtilsRuntimePatch();
-
 const program /*: Command */ = require('./cli.flow.js').default;
 
 if (require.main === module) {

packages/core-cli-utils/src/index.flow.js

@@ -55,6 +55,7 @@
     "@react-native-community/cli": "20.0.0",
     "@react-native-community/cli-platform-android": "20.0.0",
     "@react-native-community/cli-platform-ios": "20.0.0",
+    "@react-native/core-cli-utils": "*",
     "commander": "^12.0.0",
     "listr2": "^6.4.1",
     "rxjs": "npm:@react-native-community/rxjs@6.5.4-custom"