chore: migrate test runner from Jest to Vitest (#617)

Replace `jest` + `ts-jest` with `vitest` for faster, more reliable test
execution.

Drops Node 16 from the CI checks (incompatibility w/ latest Vitest
through missing `crypto` API).

Closes #612

Author: barjin

.github/workflows/test_and_release.yaml

@@ -15,7 +15,7 @@ jobs:
         strategy:
             fail-fast: false
             matrix:
-                node-version: [ 16, 18, 20, 22 ]
+                node-version: [ 18, 20, 22 ]
 
         steps:
             -   uses: actions/checkout@v6
@@ -42,7 +42,7 @@ jobs:
 
         steps:
             -   uses: actions/checkout@v6
-            -   name: Use Node.js 20
+            -   name: Use Node.js
                 uses: actions/setup-node@v6
                 with:
                     node-version: 24
@@ -68,7 +68,7 @@ jobs:
 
         steps:
             -   uses: actions/checkout@v6
-            -   name: Use Node.js 20
+            -   name: Use Node.js
                 uses: actions/setup-node@v6
                 with:
                     node-version: 24
@@ -108,6 +108,6 @@ jobs:
                 with:
                     workflow: publish_to_npm.yaml
                     inputs: >
-                        { 
-                            "ref": "master" 
+                        {
+                            "ref": "master"
                         }

CLAUDE.md

@@ -11,10 +11,10 @@ Internal Apify monorepo of shared TypeScript utilities and constants published a
 ```bash
 npm install              # Install all dependencies
 npm run build            # Build all packages (lerna run build)
-npm test                 # Run all tests (jest --silent)
+npm test                 # Run all tests (vitest)
 npm run test-cov         # Run tests with coverage
-npx jest test/consts.test.ts              # Run a single test file
-npx jest test/consts.test.ts -t "pattern" # Run specific test by name
+npx vitest run test/consts.test.ts              # Run a single test file
+npx vitest run test/consts.test.ts -t "pattern" # Run specific test by name
 npm run lint             # Lint all source and test files
 npm run lint:fix         # Lint with auto-fix
 npm run clean            # Clean all dist/ folders
@@ -29,10 +29,10 @@ npm run clean            # Clean all dist/ folders
 
 ## Key Conventions
 
-- **Imports in tests:** Always use absolute package names (`@apify/consts`, not relative paths to package sources). Jest's `moduleNameMapper` resolves `@apify/*` to `packages/*/src`
+- **Imports in tests:** Always use absolute package names (`@apify/consts`, not relative paths to package sources). Vitest's `resolve.alias` resolves `@apify/*` to `packages/*/src`
 - **Cross-package imports in source:** Use absolute `@apify/*` paths. Within the same package, use relative imports. Never self-import a package by its own `@apify/*` name
 - **Dev dependencies** go in the root `package.json` only. Runtime dependencies go in each package's own `package.json`
-- **No build needed for tests** — ts-jest compiles TypeScript directly from source
+- **No build needed for tests** — Vitest compiles TypeScript directly from source via esbuild
 - **Conventional commits** required: `fix:` (patch), `feat:` (minor), `BREAKING CHANGE:` in footer (major). Enforced by commitlint + husky hooks. PR titles must also follow this format
 - **Adding a new package:** Copy an existing package directory, update `package.json` name/deps, keep the standard `build`/`clean`/`compile`/`copy` scripts
 - Package dependencies must be declared in `package.json` so Lerna builds in correct topological order