This PR introduces an environment variable that allows to modify the `EdgeRuntime` value on compilation time.
This is done to allow cloud providers like Vercel to have a different value, and enable user code and 3rd party libraries to have different code paths depending on the Edge Functions provider.
## Related
- Related to #30739
## Bug
- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`
this commit allows to use EdgeRuntime as a dead code eliminator identifier:
```ts
if (typeof EdgeRuntime !== "undefined") {
console.log("will be stripped away");
} else {
console.log("will be kept in the bundle");
}
```
which means we're replacing `EdgeRuntime` with a literal
## Related
- Fixes#30739
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [x] Related issues linked using `fixes #number`
- [x] 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 `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
