@ is an illegal character in external javascript module name

[ofekd]

This is needed when importing scoped packages which start with @.

I could open a PR and add @ as a character to the regex, but isn't it better to just allow anything, and leave the resolution to the bundler/runtime?

In Linux, for example, almost any character is a legal filename, and therefore someone somewhere must have a very weirdly-named JS file that they want to use in an @export.

[lpil]

Thank you