fix(worker): support UTF-8 encoding in inline workers (fixes #12117)

[xiaohk]

Description

This PR fixes #12117. It's based on PR #12122. This PR allows inline worker to include UTF-8 characters.

Additional context

This PR rebases #12122 into main and adds a test.

superseds close #12122

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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, especially the Pull Request Guidelines.
• 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).
• Update the corresponding documentation if needed.
• Ideally, include relevant tests that fail without this PR but pass with it.

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[sapphi-red]

Thanks!