feat(dev-infra): create format tool in @angular/dev-infra-private (#36726)

Previously we used gulp to run our formatter, currently clang-format,
across our repository.  This new tool within ng-dev allows us to
migrate away from our gulp based solution as our gulp solution had
issue with memory pressure and would cause OOM errors with too large
of change sets.

PR Close #36726

dev-infra/format/cli.ts

@@ -0,0 +1,45 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+import * as yargs from 'yargs';
+
+import {allChangedFilesSince, allFiles} from '../utils/repo-files';
+
+import {checkFiles, formatFiles} from './format';
+
+/** Build the parser for the format commands. */
+export function buildFormatParser(localYargs: yargs.Argv) {
+  return localYargs.help()
+      .strict()
+      .demandCommand()
+      .option('check', {
+        type: 'boolean',
+        default: process.env['CI'] ? true : false,
+        description: 'Run the formatter to check formatting rather than updating code format'
+      })
+      .command(
+          'all', 'Run the formatter on all files in the repository', {},
+          ({check}) => {
+            const executionCmd = check ? checkFiles : formatFiles;
+            executionCmd(allFiles());
+          })
+      .command(
+          'changed [shaOrRef]', 'Run the formatter on files changed since the provided sha/ref', {},
+          ({shaOrRef, check}) => {
+            const sha = shaOrRef || 'master';
+            const executionCmd = check ? checkFiles : formatFiles;
+            executionCmd(allChangedFilesSince(sha));
+          })
+      .command('files <files..>', 'Run the formatter on provided files', {}, ({check, files}) => {
+        const executionCmd = check ? checkFiles : formatFiles;
+        executionCmd(files);
+      });
+}
+
+if (require.main === module) {
+  buildFormatParser(yargs).parse();
+}