[Bug]: Support for static keyword so that not multiple copies will be created of that variable

### Describe the bug

As we have in Java static keyword , is there any keyword to support it ? Or maybe we need to introduce new decorator as static

### Reproduction

NA

### Checklist

- [X] Follow our [Code of Conduct](https://github.com/microsoft/typespec/blob/main/CODE_OF_CONDUCT.md)
- [X] Check that there isn't already an issue that request the same bug to avoid creating a duplicate.
- [X] Check that this is a concrete bug. For Q&A open a [GitHub Discussion](https://github.com/Microsoft/typespec/discussions).
- [X] The provided reproduction is a [minimal reproducible example](https://stackoverflow.com/help/minimal-reproducible-example) of the bug.