Restore cli-kit root export

[mojobeeping]

What

Restores the missing @shopify/cli-kit root entry by adding packages/cli-kit/src/index.ts with the documented file and path namespaces.

The published @shopify/cli-kit@4.1.0 package still advertises:

• exports["."].import = ./dist/index.js
• exports["."].types = ./dist/index.d.ts
• module = dist/index.js
• types = dist/index.d.ts

but the tarball does not include dist/index.js or dist/index.d.ts, so import('@shopify/cli-kit') fails in a clean install.

This also re-adds the local TS path mapping for the root package and updates the testing-strategy docs sample to use the current filesystem/path helper names.

Reproduction

mkdir /tmp/cli-kit-root-repro
cd /tmp/cli-kit-root-repro
npm init -y
npm install --ignore-scripts @shopify/cli-kit@4.1.0
node -e "import('@shopify/cli-kit').catch(e => { console.error(e.code + ': ' + e.message); process.exit(1) })"

Current output:

ERR_MODULE_NOT_FOUND: Cannot find module '.../node_modules/@shopify/cli-kit/dist/index.js'

Validation

• pnpm --filter @shopify/cli-kit vitest src/index.test.ts
• pnpm --filter @shopify/cli-kit build
• pnpm --filter @shopify/cli-kit lint
• git diff --check
• npm pack --ignore-scripts --json --pack-destination /tmp/mojobeep-shopify-cli-kit-patched-pack
• Clean packed-tarball install: import('@shopify/cli-kit') exposes file.inTemporaryDirectory, file.writeFile, and path.joinPath
• Clean packed-tarball TypeScript consumer with skipLibCheck: false and @types/react@19 resolves import {file, path} from '@shopify/cli-kit'

[mojobeeping]

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