clarify difference between tracked and interned structs

Author: ibraheemdev

src/tracked_struct.rs

@@ -146,10 +146,14 @@ pub trait TrackedStructInDb: SalsaStructInDb {
 /// This ingredient only stores the "id" fields. It is a kind of "dressed up" interner;
 /// the active query + values of id fields are hashed to create the tracked
 /// struct id. The value fields are stored in [`crate::function::IngredientImpl`]
-/// instances keyed by the tracked struct id. Unlike normal interners, tracked
-/// struct indices can be deleted and reused aggressively: when a tracked
-/// function re-executes, any tracked structs that it created before but did
-/// not create this time can be deleted.
+/// instances keyed by the tracked struct id.
+///
+/// Unlike normal interned values, tracked struct indices can be deleted and reused aggressively
+/// without dependency edges on the creating query. When a tracked function is collected,
+/// any tracked structs it created can be deleted. Additionally, when a tracked function
+/// re-executes but does not create a tracked struct that was previously created, it can
+/// be deleted. No dependency edge is required as the lifetime of a tracked struct is tied
+/// directly to the query that created it.
 pub struct IngredientImpl<C>
 where
     C: Configuration,