note breaking props.children change

Author: Rich-Harris

sites/svelte-5-preview/src/routes/docs/content/01-api/03-snippets.md

@@ -215,6 +215,8 @@ Any content inside the component tags that is _not_ a snippet declaration implic
 </table>
 ```
 
+> Note that you cannot have a prop called `children` if you also have content inside the component — for this reason, you should avoid having props with that name
+
 ## Snippets and slots
 
 In Svelte 4, content can be passed to components using [slots](https://svelte.dev/docs/special-elements#slot). Snippets are more powerful and flexible, and as such slots are deprecated in Svelte 5.

sites/svelte-5-preview/src/routes/docs/content/03-appendix/02-breaking-changes.md

@@ -54,6 +54,10 @@ Svelte now use Mutation Observers intead of IFrames to measure dimensions for `b
 - The `tag` option was removed. Use `<svelte:options customElement="tag-name" />` inside the component instead
 - The `loopGuardTimeout`, `format`, `sveltePath`, `errorMode` and `varsReport` options were removed
 
+## The `children` prop is reserved
+
+Content inside component tags becomes a [snippet prop](/docs/snippets) called `children`. You cannot have a separate prop by that name.
+
 ## Other breaking changes
 
 ### Stricter `@const` assignment validation