use u64 instead of usize in checksums

src/rollback.rs

@@ -56,15 +56,15 @@ impl<'w, 's, 'a> AddRollbackCommandExtension for EntityCommands<'w, 's, 'a> {
 /// A [`Resource`] which provides methods for stable ordering of [`Rollback`] flags.
 #[derive(Resource, Default, Clone)]
 pub struct RollbackOrdered {
-    order: HashMap<Rollback, usize>,
+    order: HashMap<Rollback, u64>,
     sorted: Vec<Rollback>,
 }
 
 impl RollbackOrdered {
     /// Register a new [`Rollback`] for explicit ordering.
     fn push(&mut self, rollback: Rollback) -> &mut Self {
         self.sorted.push(rollback);
-        self.order.insert(rollback, self.sorted.len() - 1);
+        self.order.insert(rollback, self.sorted.len() as u64 - 1);
 
         self
     }
@@ -75,7 +75,7 @@ impl RollbackOrdered {
     }
 
     /// Returns a unique and order stable index for the provided [`Rollback`].
-    pub fn order(&self, rollback: Rollback) -> usize {
+    pub fn order(&self, rollback: Rollback) -> u64 {
         self.order
             .get(&rollback)
             .copied()

src/snapshot/entity_checksum.rs

@@ -19,10 +19,10 @@ impl EntityChecksumPlugin {
         let mut hasher = checksum_hasher();
 
         // The quantity of active rollback entities must be synced.
-        active_entities.iter().len().hash(&mut hasher);
+        (active_entities.iter().len() as u64).hash(&mut hasher);
 
         // The quantity of total spawned rollback entities must be synced.
-        rollback_ordered.len().hash(&mut hasher);
+        (rollback_ordered.len() as u64).hash(&mut hasher);
 
         let result = ChecksumPart(hasher.finish() as u128);