Move to a generic GlobalLazy<T> (#2851)

* Expose a generic lazy type

* Switch to generic lazy globals

* simplify global lazy context a bit

* rename LazyGlobal to Global

* use Memo::global in more examples

* Fix soundness issue with deref_impl. It relies on the size of self, so it cannot be safe

* add a comment about safety

* Make clippy happy

* fix formatting

* Restore changes to signal impl

* Add helper methods for global signal and global memo to make getting the inner value easier

packages/signals/src/signal.rs

@@ -1,4 +1,4 @@
-use crate::{default_impl, fmt_impls, write_impls};
+use crate::{default_impl, fmt_impls, write_impls, Global};
 use crate::{read::*, write::*, CopyValue, GlobalMemo, GlobalSignal, ReadableRef};
 use crate::{Memo, WritableRef};
 use dioxus_core::prelude::*;
@@ -87,7 +87,7 @@ impl<T: 'static> Signal<T> {
     /// </div>
     #[track_caller]
     pub const fn global(constructor: fn() -> T) -> GlobalSignal<T> {
-        GlobalSignal::new(constructor)
+        Global::new(constructor)
     }
 }
 
@@ -118,7 +118,10 @@ impl<T: PartialEq + 'static> Signal<T> {
     ///
     /// </div>
     #[track_caller]
-    pub const fn global_memo(constructor: fn() -> T) -> GlobalMemo<T> {
+    pub const fn global_memo(constructor: fn() -> T) -> GlobalMemo<T>
+    where
+        T: PartialEq,
+    {
         GlobalMemo::new(constructor)
     }
 
@@ -462,7 +465,7 @@ impl<T: Clone, S: Storage<SignalData<T>> + 'static> Deref for Signal<T, S> {
     type Target = dyn Fn() -> T;
 
     fn deref(&self) -> &Self::Target {
-        Readable::deref_impl(self)
+        unsafe { Readable::deref_impl(self) }
     }
 }