refactor: organise TypeScript config and migrate helpers (#44747)

* feat: allow more 1000 steps to be created at once

* refactor: start migrating to typescript

* refactor: delete-step to ts

* refactor: migrated some helpers

* refactor: migrate create-empty-steps

* refactor: migrate create-step-between

* refactor: finish migrating to TS

* refactor: migrate tests

* fix: ensure mock.restore is done after each test

* fix: prevent double-tscing

* fix: repair the tests

* chore: use ts-node for scripts

We don't need the performance boost of incremental compilation and
ts-node is easier to work with

* refactor: consolidate tsconfigs

* refactor: replace gulp

* fix: use ts-node for build-curriculum

* fix: allow ts compilation of config

* feat: create and use create:config script

* fix: add /config to eslint projects

* fix: remove gulp script

tools/challenge-helper-scripts/helpers/get-project-path.test.ts

@@ -0,0 +1,22 @@
+import { getProjectPath } from './get-project-path';
+
+describe('getProjectPath helper', () => {
+  it('should return the calling dir path', () => {
+    const mockCallingDir = 'calling/dir';
+    const expected = `${mockCallingDir}/`;
+
+    // Add mock to test condition
+    process.env.CALLING_DIR = mockCallingDir;
+
+    expect(getProjectPath()).toEqual(expected);
+
+    // Remove mock to not affect other tests
+    delete process.env.CALLING_DIR;
+  });
+
+  it('should return the projects absolute path', () => {
+    const expected = `${process.cwd()}/`;
+
+    expect(getProjectPath()).toEqual(expected);
+  });
+});