fix: quick add opens create ui

Add createKey to quick-add manifests and client create dialog host.

FAB and command palette open in-place create UIs instead of navigating away.

src/modules/_core/module.ts

@@ -67,6 +67,8 @@ export type QuickAddAction = {
   icon?: string;
   /** Navigation target used by the FAB sheet and command palette. */
   url: string;
+  /** Client-side create dialog key (see quick-add create registry). */
+  createKey?: string;
   action?: (ctx: WidgetContext) => void | Promise<void>;
 };