chore(changelog): Remove ##Unreleased section

[Lms24]

The unreleased section interferes with automatic changelog generation.RIP office quote :(

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

📋 Changelog Preview

This is how your changes will appear in the changelog.
Entries from this PR are highlighted with a left border (blockquote style).

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New Features ✨

• Inject component annotations into HTML elements rather than React components by timfish in #851
• Combine injection snippets by timfish in #853
• Use Rolldown native MagicString by timfish in #846

Internal Changes 🔧

• (changelog) Remove ##Unreleased section by Lms24 in #856

• (release) Fix changelog-preview permissions by BYK in #852

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_{🤖 This preview updates automatically when you update the PR.}

[andreiborza]