feat: Trait::hasInitialized

packages/entity/trait.js

@@ -34,6 +34,8 @@ export class Trait {
 
   destroy() {}
 
+  hasInitialized() {}
+
   hooks() {
     return {};
   }

packages/entity/traits/index.js

@@ -116,6 +116,8 @@ export class Traits {
       properties[key].instance = instance;
       this.properties_PRIVATE[key] = properties[key];
     }
+    // Let the Trait know that it has initialized.
+    instance.hasInitialized();
     // Add state.
     this._setInstanceState(type, instance);
     // Track trait.