feat: update challenge helpers to handle id filenames (#44769)

* refactor: light tweaks for readability

* refactor: simplify metadata functions

* fix: most tests

* test: fix utils tests

* test: simplify mocks

* WIP: update get-last-step-file-content

* feat: finish create-next-step

* fix: type error

* test: provide mock meta.json for test

* refactor: get meta path from project path

* refactor: get project name from path

* refactor: simplify getProjectMetaPath further

Also removes some excessive mocking

* refactor: remove more mocks, always clear .env

* feat: update create-next-step

* feat: update create-empty steps

Also refactors slightly, so it's easier to insert steps into the meta

* docs: update challenge-helper-script docs

* feat: create-step-between

* refactor: allow metadata parse errors to propagate

* fix: convert reorderSteps to renameSteps

* refactor: create-step-between -> insert-step

* feat: update delete-step

* refactor: consolidate commands into commands.ts

* refactor: clean up and consolidation

* refactor: more cleanup

* fix: make cli args consistent

Everything accepts a single integer and nothing else

* refactor: renameSteps -> updateStepTitles

* docs: update with the names and args

* feat: add step validating meta + files are synced

tools/challenge-helper-scripts/helpers/get-last-step-file-number.ts

@@ -0,0 +1,13 @@
+import { last } from 'lodash';
+import { getMetaData } from './project-metadata';
+
+function getLastStep(): { stepNum: number } {
+  const meta = getMetaData();
+  const challengeOrder: string[][] = meta.challengeOrder;
+  const step = last(challengeOrder);
+  if (!step) throw new Error('No steps found');
+
+  return { stepNum: challengeOrder.length };
+}
+
+export { getLastStep };