docs: add ngmodule api doc (#25618)

PR Close #25618

packages/platform-browser/animations/src/module.ts

@@ -11,7 +11,9 @@ import {BrowserModule} from '@angular/platform-browser';
 import {BROWSER_ANIMATIONS_PROVIDERS, BROWSER_NOOP_ANIMATIONS_PROVIDERS} from './providers';
 
 /**
- * @experimental Animation support is experimental.
+ * Exports `BrowserModule` with additional [dependency-injection providers](guide/glossary#provider)
+ * for use with animations. See [Animations](guide/animations).
+ * @experimental
  */
 @NgModule({
   exports: [BrowserModule],
@@ -21,7 +23,8 @@ export class BrowserAnimationsModule {
 }
 
 /**
- * @experimental Animation support is experimental.
+ * A null player that must be imported to allow disabling of animations.
+ * @experimental
  */
 @NgModule({
   exports: [BrowserModule],

packages/platform-browser/src/browser.ts

@@ -89,7 +89,11 @@ export const BROWSER_MODULE_PROVIDERS: StaticProvider[] = [
 ];
 
 /**
- * The ng module for the browser.
+ * Exports required infrastructure for all Angular apps.
+ * Included by defaults in all Angular apps created with the CLI
+ * `new` command.
+ * Re-exports `CommonModule` and `ApplicationModule`, making their
+ * exports and providers available to all apps.
  *
  *
  */
@@ -103,9 +107,12 @@ export class BrowserModule {
   }
 
   /**
-   * Configures a browser-based application to transition from a server-rendered app, if
-   * one is present on the page. The specified parameters must include an application id,
-   * which must match between the client and server applications.
+   * Configures a browser-based app to transition from a server-rendered app, if
+   * one is present on the page.
+   *
+   * @param params An object containing an identifier for the app to transition.
+   * The ID must match between the client and server versions of the app.
+   * @returns The reconfigured `BrowserModule` to import into the app's root `AppModule`.
    *
    * @experimental
    */