add must use to several hooks

packages/fermi/src/hooks/read.rs

@@ -2,10 +2,12 @@ use crate::{use_atom_root, AtomId, AtomRoot, Readable};
 use dioxus_core::{ScopeId, ScopeState};
 use std::rc::Rc;
 
+#[must_use]
 pub fn use_read<V: 'static>(cx: &ScopeState, f: impl Readable<V>) -> &V {
     use_read_rc(cx, f).as_ref()
 }
 
+#[must_use]
 pub fn use_read_rc<V: 'static>(cx: &ScopeState, f: impl Readable<V>) -> &Rc<V> {
     let root = use_atom_root(cx);