fix(core): allow dynamically added options to receive keyboard focus

Author: adamjohnson

core/pfe-core/controllers/at-focus-controller.ts

@@ -118,6 +118,14 @@ export abstract class ATFocusController<Item extends HTMLElement> {
     this.itemsContainerElement ??= this.#initContainer();
   }
 
+  /**
+   * Refresh items from the getItems option. Call this when the list of items
+   * has changed (e.g. when a parent controller sets items).
+   */
+  refreshItems(): void {
+    this.initItems();
+  }
+
   hostConnected(): void {
     this.hostUpdate();
   }

core/pfe-core/controllers/combobox-controller.ts

@@ -281,6 +281,7 @@ export class ComboboxController<
 
   set items(value: Item[]) {
     this.#lb.items = value;
+    this.#fc?.refreshItems?.();
   }
 
   /** Whether the combobox is disabled */