Replace ambient declaration file (index.d.ts) with generated type definitions

[colebemis]

Problem

Primer React components was originally released without TypeScript type definitions, making it difficult for engineers to consume the library in TypeScript applications. In July 2019, we created an ambient declaration file (index.d.ts) file to provide type definitions for TypeScript applications without having to rewrite Primer React components in TypeScript.

index.d.ts has been an effective stopgap, enabling teams to build complex applications with Primer React components and TypeScript. However, because index.d.ts is disconnected from the implementation code, we've struggled to keep the type definitions up-to-date and accurate, as evidenced by many TypeScript bug reports. As the library continues to grow in size and complexity, manually maintaining type definitions will become unsustainable.

Solution

Now that all our components have been rewritten in TypeScript, we can use the TypeScript compiler to generate type definitions instead of manually maintaining an ambient declaration file. This PR removes our manually maintained index.d.ts file and updates the package.json to reference the generated type definitions.

TODO

• Test in memex

[changeset-bot]

🦋 Changeset detected

Latest commit: f859862

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/components	Major

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[colebemis]

This branch is stale. Closing in favor of #1147