Add "bun:" escape hatch to node resolver. Resolves #14351

[andrioid]

Description

Allow Vite to resolve internal bun: packages. Resolves #14351

Additional context

I'd love to improve this, if needed. It's a pretty straight forward change. Maybe maintainers want to make a more robust way of excluding packages from the node resolver plugin?

---

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the PR Title Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

[stackblitz]

Run & review this pull request in StackBlitz Codeflow.

[andrioid]

Sorry. I thought I could quickly pull this off using GitHub Codespaces. But the formatting is all messed up. I'll fix it as soon as I have the time to work on it locally.