`MODULE_LEVEL_DIRECTIVE` warning during build

Astro Info

Astro                    v7.3.3
Node                     v24.20.0
System                   macOS (arm64)
Package Manager          pnpm
Output                   static
Adapter                  none
Integrations             @astrojs/starlight

If this issue only occurs in one browser, which browser is a problem?

No response

Describe the Bug

When creating a new Starlight project and running the build command, I get the following warning:

18:30:37 [build] Building static entrypoints...
18:30:38 [WARN] [vite] [MODULE_LEVEL_DIRECTIVE] The semantics of the module level directive "use astro:head-inject" in "src/content/docs/index.mdx?astroPropagatedAssets" may not be preserved when bundling.
   ╭─[ src/content/docs/index.mdx?astroPropagatedAssets:2:6 ]
   │
   2 │               "use astro:head-inject";
   │               ────────────┬───────────
   │                           ╰───────────── module level directive may not be preserved
   │
   │ Help: For more information, see https://rolldown.rs/in-depth/directives#other-directives
───╯

18:30:38 [vite] ✓ built in 498ms

I guess technically it could happen in any Astro project and not only in Starlight projects.

What's the expected result?

No warning.

Link to Minimal Reproducible Example

https://github.com/HiDeoo/astro-module-level-directive-warning-repro

Participation

• I am willing to submit a pull request for this issue.