Add rewrite frames integration

We could add a rewrite frames integration similar to [javascript]() that allows users to manipulate the frames in a specific way before sending them off.

### Examples of what it would solve

Relates to [https://github.com/getsentry/sentry-dart-plugin/pull/222]()

When users provide a `urlPrefix` with `sentry-dart-plugin` and `sentry-cli`, stack traces are not resolved correctly, as the path cant be found.

the stack trace abs path is `"http://localhost: 8900/main.dart`.
the uploaded file is `~/foo/main.dart` -> doesn't match

so you would need to rewrite the abs_path to the uploaded file to include the prefix.

With a rewrite frame integration it would be easy to do that.

### Alternatives

Use beforeSend code snippet

```dart
beforeSendCallback: (event, hint) async {
final exceptions = event.exceptions?.map((exception) {
final stackTrace = exception.stackTrace;
if (stackTrace != null) {
final frames = stackTrace.frames.map((frame) {
const baseUrl = 'https://example.com/';
final modifiedAbsPath = frame.absPath?.replaceFirst(baseUrl, '${baseUrl}my_prefix/');
return frame.copyWith(absPath: modifiedAbsPath);
}).toList();
return exception.copyWith(stackTrace: SentryStackTrace(frames: frames));
}
return exception;
}).toList() ?? [];
return event.copyWith(exceptions: exceptions);
});
```

### Demand

Please upvote if you are interested in such an integration