add release note

release-content/release-notes/new_querydata.md

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+---
+title: New QueryData Types
+authors: ["@ecoskey"]
+pull_requests: [19602]
+---
+
+Bevy queries have some new powers for advanced users. Namely, custom `WorldQuery`
+implementations can store and apply "deferred" mutations, just like `Commands`!
+This release includes a few new types making use of this capability, and
+we're sure third-party crates will find all kinds of new ways to do cool stuff
+with this.
+
+## `DeferredMut`
+
+When working with immutable components in Bevy, the acts of reading and writing
+component values are very clearly separated. This can be valuable, especially
+if a component has expensive hooks or observers attached and `insert`ing it
+has a significant cost, but in some cases it can feel like boilerplate.
+
+`DeferredMut` is meant to improve the ergonomics of the latter case, by providing
+"fake" mutable access to any component, even immutable ones! Internally, it
+keeps track of any modifications and inserts them into the ECS at the next
+sync point.
+
+```rs
+// without `DeferredMut`
+pub fn tick_poison(
+    mut commands: Commands,
+    query: Query<(Entity, &Health), With<Poisoned>>
+) {
+    for (entity, Health(health_points)) in query {
+        commands.insert(entity, Health(health_points - 1))
+    }
+}
+
+// with `DeferredMut`
+pub fn tick_poison(
+    mut health_query: Query<DeferredMut<Health>, With<Poisoned>>
+) {
+    for mut health in &health_query {
+         health.0 -= 1;
+    }
+}
+   
+```