feat(types): Better typescript support for emit `events`

[pikax]

Requires [email protected]

NOTE: There's some build errors when updating to [email protected], this PR is not meant to fix those errors, only to implement string type inference

[pikax]

I believe the build is failing because of usage of Typescript ^4.1.x with @microsoft/api-extractor

[yyx990803]

@pikax mind rebasing on latest 3.2 branch?

[edison1105]

Could you please resolve those conflicts？