docs: add caution about scripts processing when using head config (#1729

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Co-authored-by: Chris Swithinbank <swithinbank@gmail.com>

docs/src/content/docs/reference/configuration.mdx

@@ -444,6 +444,9 @@ starlight({
 });
 ```
 
+Entries in `head` are converted directly to HTML elements and do not pass through Astro’s [script](https://docs.astro.build/en/guides/client-side-scripts/#script-processing) or [style](https://docs.astro.build/en/guides/styling/#styling-in-astro) processing.
+If you need to import local assets like scripts, styles, or images, [override the Head component](/guides/overriding-components/#reuse-a-built-in-component).
+
 #### `HeadConfig`
 
 ```ts