Fix side-by-side fragments by walking in reverse (#2841)

* got a repro, but no solution :(

* hmmmmm 🤔

* awyayayayayayya

* omg it's because we dont create in rev

* Make nodes rev

* fix tests compile

* Clean up PR

* revert changes to native

* Clean up PR, add test

packages/interpreter/src/write_native_mutations.rs

@@ -97,14 +97,17 @@ impl WriteMutations for MutationState {
     fn load_template(&mut self, template: Template, index: usize, id: dioxus_core::ElementId) {
         // Get the template or create it if we haven't seen it before
         let tmpl_id = self.templates.get(&template).cloned().unwrap_or_else(|| {
-            let current_max_template_count = self.templates.len() as u16;
+            let tmpl_id = self.templates.len() as u16;
+            self.templates.insert(template, tmpl_id);
+
             for root in template.roots.iter() {
                 self.create_template_node(root);
-                self.templates.insert(template, current_max_template_count);
             }
-            let id = template.roots.len() as u16;
-            self.channel.add_templates(current_max_template_count, id);
-            current_max_template_count
+
+            let len = template.roots.len() as u16;
+            self.channel.add_templates(tmpl_id, len);
+
+            tmpl_id
         });
 
         self.channel