Publish valid ESM types for dual output packages

[cuzzlor]

Problem

https://arethetypeswrong.github.io/?p=%40makerx%2Fexpress-msal%40%5E2.0.0-beta.0

More details

https://github.com/arethetypeswrong/arethetypeswrong.github.io/blob/main/docs/problems/FalseCJS.md

Solution

• fix(types): emit dual type declarations
• feature: add check-exports build step to template output

[Copilot]

Pull request overview

This PR updates ts-toolkit’s packaging workflow to publish valid TypeScript declarations for dual ESM/CJS outputs and adds an arethetypeswrong export/types validation step to generated templates and this repo’s build.

Changes:

• Emit conditional exports entries with per-condition types for dual-output packages.
• Add a build step to validate published artifacts with @arethetypeswrong/cli (attw --pack dist), including wiring it into templates and devDependencies.
• Add utilities + tests to generate .d.mts/.d.cts siblings and rewrite relative specifiers for ESM declaration resolution.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/util/copy-package-json-from-config.ts	Builds new exports shapes and emits dual declaration siblings with ESM-specifier rewriting.
src/util/copy-package-json-from-config.spec.ts	Adds tests for conditional exports shapes and declaration emission/rewriting.
src/init/check-packages.ts	Ensures @arethetypeswrong/cli is installed in initialized Node projects.
src/init/add-scripts.ts	Adds build:* script to run attw against the packed dist output in templates.
package.json	Bumps version and adds attw build script + devDependency.
package-lock.json	Locks new @arethetypeswrong/cli dependency tree and updates version metadata.

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[cuzzlor]

This worked well