Variables are not recognized inside string interpolation if <style> is part of the string

[sserdyuk]

Describe the bug

I needed to dynamically define CSS variables based on the config, and I used string interpolation to construct an HTML fragment and insert it at svelte:head. While it works, it confuses the VS Code plugin. First, the branding variable is marked as unused, second there's no type information during interpolation. After some experiments, I found that <style> in the string is what triggering the issue.

Reproduction

<script lang="ts">
  const config = { branding: { primaryColor: '#012345' } },
    branding = config?.branding;

  const cssString = `<style>:root {--primary-color: ${branding?.primaryColor ?? '#ABCDEF'};}</style>`;
</script>

<svelte:head>
  {@html cssString}
</svelte:head>

Expected behaviour

I was expecting that string interpolation works regardless the content of the string.

System Info

• OS: [e.g. Windows]
• IDE: [e.g. VSCode, Atom]

Which package is the issue about?

Svelte for VS Code extension

Additional Information, eg. Screenshots

No response