fix: Improve DOM-less type exports (#352)

Usage of HeadersInit requires either a node-fetch dependency or to
include DOM in tsconfig libs for consumer projects. It is not exported
as a global type in @types/node v18 or v20. RequestInit is:

https://github.com/DefinitelyTyped/DefinitelyTyped/blob/aaf94a0a6431f52c46dab26182f1156d79720d29/types/node/v18/globals.d.ts#L341

Define headers in interface HTTPResolverOptions<> via
RequestInit['headers'] which will make it possible to depend on this
project without node-fetch.

fix: bump deps

fix: create release and bump deps

fix: fix path sep undefined #345

minimum repro of bundle error for bug with json schema validator site

chore: disable flaky tests

fix(types): make default type extend base object instead of JSONSchem…

…a to support non-spec compliant type overloads

fix(types): fix types of options, inheritance globally

fix(types): fix types to accept spread or list of strings

fix(types): add correct extends in all places, make all generic