Native Kotlin Multiplatform support

Instead of adding bindings, it would be great if we had native Kotlin Multiplatform support. More then we can use pkl in more scenarios.

For example, I am considering using pkl to provide i18n in my Kotlin Multiplatform project.

We can follow [this](https://github.com/JetBrains/markdown/tree/master?tab=readme-ov-file#development-gotchas) to implement a native Kotlin lexer.

Start by reviewing the linked JetBrains Markdown development gotchas and the request for a native Kotlin lexer. The work is complete when Pkl has native Kotlin Multiplatform support rather than bindings, including the lexer needed for the stated i18n use case.

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