Autocomplete rsx

[ealmloff]

Autocompleting RSX

This PR changes the expansion of rsx slightly to enable rust analyzer to autocomplete elements, attributes, components and braces while you type partially based on this blog post. Our macro is still ambiguous while typing the first element/last attribute

rsx! {
    div {
        w // It isn't clear while you are typing if you are making an attribute or an element
    }
}

To get around this, we create a completions module that can expand to both an attribute or element and let the user choose.

It also fixes a few span issues causing confusing error messages when a component prop is missing or the definition of an event handler closure was incorrect

Screen.Recording.2024-05-16.at.4.42.56.PM.mov

Breaking changes

This PR includes breaking changes to the rsx macro which requires changes in all dioxus_element structures. This will only effect libraries that define a custom set of elements for dioxus to use

Fixes #2422