fix(ivy): correctly export all *Def symbols as private (#24862)

Previously, some of the *Def symbols were not exported or were exported
as public API. This commit ensures every definition type is in the
private export namespace.

PR Close #24862

tools/public_api_guard/core/core.d.ts

@@ -408,12 +408,6 @@ export declare abstract class Injector {
 /** @experimental */
 export declare const INJECTOR: InjectionToken<Injector>;
 
-export interface InjectorDef<T> {
-    factory: () => T;
-    imports: (InjectorType<any> | InjectorTypeWithProviders<any>)[];
-    providers: (Type<any> | ValueProvider | ExistingProvider | FactoryProvider | ConstructorProvider | StaticClassProvider | ClassProvider | any[])[];
-}
-
 /** @experimental */
 export interface InjectorType<T> extends Type<T> {
     ngInjectorDef: never;