docs: clarify how Reference::peeled is working.

Author: Byron

gix-ref/src/raw.rs

@@ -10,7 +10,9 @@ pub struct Reference {
     pub name: FullName,
     /// The target of the reference, either a symbolic reference by full name or a possibly intermediate object by its id.
     pub target: Target,
-    /// The fully peeled object to which this reference ultimately points to. Only guaranteed to be set after `peel_to_id_in_place()` was called.
+    /// The fully peeled object to which this reference ultimately points to. Only guaranteed to be set after
+    /// [`Reference::peel_to_id_in_place()`](crate::file::ReferenceExt) was called or if this reference originated
+    /// from a packed ref.
     pub peeled: Option<ObjectId>,
 }