* feat: make `<svelte:component>` unnecessary in runes mode
In Svelte 4, writing `<Component />` meant that the component instance is static. If you made the variable `Component` a reactive state variable and updated the component value, the component would not be reinstantiated with the new value - you had to use `<svelte:component>` for that. One reason was that having a dynamic component was more overhead, which is no longer the case in Svelte 5. We can therefore reduce the potential API surface area (by maybe deprecating `<svelte:component>` in the future) by allowing Svelte to recognize when a component variable is potentially dynamic. It turned out that this was already mostly the case. This PR fixes one case where it wasn't, and fixes another where this was wrongfully applied in legacy mode.
* we already have this function
* add interactive demos
* changeset
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Co-authored-by: Rich Harris <rich.harris@vercel.com>