Typescript declaration file is not included in package on install

[dcavanagh]

I did:

• Search for if my issue has already been submitted
• Make sure I'm reporting something precise that needs to be fixed
• Give my issue a descriptive and concise title
• Create a minimal working example on JsFiddle or Codepen
  (or gave a link to a demo on the Selectize docs)
• Indicate precise steps to reproduce in numbers and the result,
  like below

[replace me with a short description of issue]

Steps to reproduce:

1. npm install @selectize/selectize
2. ls node_modules/@selectize/selectize

Expected result:
LICENSE README.md dist index.d.ts package.json

Actual result:
LICENSE README.md dist package.json

index.d.ts is missing from the directory and is needed when using typescript

[github-actions]

This issue is stale because it has been open 90 days with no activity. Remove stale label or comment or this will be closed in 5 days

[cpsievert]

I would like to see this problem fixed

[github-actions]

This issue is stale because it has been open 90 days with no activity. Remove stale label or comment or this will be closed in 5 days

[dvg-p4]

This is still an issue, and seems relatively straightforward to fix?

[dvg-p4]

Currently the lack of a typescript definition file can be worked around by using the definition file from https://github.com/DefinitelyTyped/DefinitelyTyped, which appears to be more up-to-date (though not completely).

[dvg-p4]

c.f. #2145 -- note that the current file's signatures are significantly out-of-date.