Fix the ssr/ssg detection when you export a nextjs data fetching method
as a variable instead of an async function.
- [x] Add case support in `checkExports`
- [x] Add unit tests for `getPageStaticInfo`
Partially implements #31317 and #31506. There're also some trade-offs made with this PR: since we can't know if a certain runtime will be used or not beforehand, we have to start both runtime compilers (Node.js and Edge) and then generate entrypoints correspondingly.
Note that with this PR, the global runtime is still required to use the per-page runtime.
## Bug
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `yarn lint`
Fixes#19862
Avoid executing `webpack` property on `loadableGenerated` of loadable component compiled from `next/dynamic` when `require.resolveWeak` is unavailable due to jest runtime missing `require.resolveWeak`.
## Bug
- [x] Related issues linked using `fixes #number`
- [x] unit tests added
