overhaul dioxus fullstack using a new implementation of server_fn
This PR is a complete rewrite of dioxus fullstack designed to improve compatibility with axum and to fix a number of compilation errors based on feature flag unification plumbing through macros.
* use DragEvent not MouseEvent for drag events
* Simplify drag events and remove WebDragData struct
* use DragEvent not MouseEvent for drag events
* re-add the web_sys event reference for drag + mouse data
* remove now vestigial impls for MouseEvent
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Co-authored-by: Matt Hunzinger <matthunz2@gmail.com>