Clean up utils/types-hoist folders from v9 migration

### Description

For v9 we hoisted `@sentry/utils` and `@sentry/types` into `@sentry/core`. We did that in a bit of a "lazy" way by dumping everything in a `utils-hoist` and `types-hoist` folder respectively and doing `export * from ...`.

Since `export * from ...` is rather error prone and makes bundlers unhappy because it makes them go look for exports, we should get rid of this patterns sooner rather than later and top-level-export all the api we intend to export.