Acceptance Criteria

• add azure/identity as an optional peer dependency to mongodb-client-encryption
• refactor the existing credential providers into separate modules, with a single index.js exporting them together
• create a new provider for azure
  • add a kms refresh function that lazily imports the azure module and fetches the credentials
  • add support for caching of the azure kms token
• add Typescript support in libmongocrypt

Testing

• lazily importing of kms providers
  • we don't import the azure module unless requested
• caching of credentials
  • we refresh the token when the token expires < 60s from the current time
  • we do not refresh the token when the token expires > 60s from the current time and return the cached token
  • if there is no cached token, we refresh the token