JSR publishing support

[williamhorning]

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Hi there! With the addition of Deno support (#2293), and the lack of dependencies on the @opentelemetry/api package, it would be nice to see support for the JSR registry, as that would allow Deno users to bypass the Node compatibility layer

It shouldn't be too difficult to do this, though from locally trying this, there are a few things that would need to be done:

1. create a jsr.json with a package name, version, and exports
2. add explicit typing to a few public exports
3. introduce the version.ts file and don't gitignore it (causes an error)
4. run cd api && npx jsr publish --no-check --allow-dirty --unstable-sloppy-imports

publishing the package shouldn't be too much work, at least for the api package, and I could submit a pr if desired. #4106 would also probably be nice but it isn't a strict requirement and also would introduce more tooling