Feat: massive changes to definition of components

This change switches back to the original `ctx<props>` syntax for
commponents. This lets lifetime elision to remove the need to match
exactly which lifetime (props or ctx) gets  carried to the output. As
such, `Props` is currently required to be static. It *is* possible to
loosen this restriction, and will be done in the future, though only
through adding metadata about the props through the Props derive
macro. Implementing the IS_STATIC trait is unsafe, so the derive macro
will do it through some heuristics.

For now, this unlocks sharing vnodes from parents to children, enabling
pass-thru components, fragments, portals, etc.

packages/core/src/lib.rs

@@ -16,8 +16,8 @@
 //! #[derive(Properties)]
 //! struct Props { name: String }
 //!
-//! fn Example(ctx: Context, props: &Props) -> DomTree {
-//!     html! { <div> "Hello {props.name}!" </div> }
+//! fn Example(ctx: Context, props: &Props) -> VNode {
+//!     html! { <div> "Hello {ctx.name}!" </div> }
 //! }
 //! ```
 //! Components need to take a "Context" parameter which is generic over some properties. This defines how the component can be used
@@ -31,8 +31,8 @@
 //! #[derive(Properties)]
 //! struct Props { name: String }
 //!
-//! static Example: FC<Props> = |ctx, props| {
-//!     html! { <div> "Hello {props.name}!" </div> }
+//! static Example: FC<Props> = |ctx| {
+//!     html! { <div> "Hello {ctx.name}!" </div> }
 //! }
 //! ```
 //!
@@ -101,7 +101,7 @@ pub(crate) mod innerlude {
     pub use crate::patch::*;
     pub use crate::virtual_dom::*;
 
-    pub type FC<P> = for<'scope> fn(Context<'scope>, &'scope P) -> DomTree;
+    pub type FC<P> = fn(Context<P>) -> VNode;
 
     // Re-export the FC macro
     pub use crate as dioxus;