[red-knot] Reduce usage of From<Type> implementations when working with Symbols (#16076)

crates/red_knot_python_semantic/src/symbol.rs

@@ -1,5 +1,5 @@
 use crate::{
-    types::{Type, UnionType},
+    types::{todo_type, Type, UnionType},
     Db,
 };
 
@@ -33,6 +33,17 @@ pub(crate) enum Symbol<'db> {
 }
 
 impl<'db> Symbol<'db> {
+    /// Constructor that creates a `Symbol` with boundness [`Boundness::Bound`].
+    pub(crate) fn bound(ty: impl Into<Type<'db>>) -> Self {
+        Symbol::Type(ty.into(), Boundness::Bound)
+    }
+
+    /// Constructor that creates a [`Symbol`] with a [`crate::types::TodoType`] type
+    /// and boundness [`Boundness::Bound`].
+    pub(crate) fn todo(message: &'static str) -> Self {
+        Symbol::Type(todo_type!(message), Boundness::Bound)
+    }
+
     pub(crate) fn is_unbound(&self) -> bool {
         matches!(self, Symbol::Unbound)
     }