refactor(cdk/menu): convert all directives to standalone (#25904)

Converts all of the `@angular/cdk/menu` directives to `standalone` so that they can be used as host directives.

(cherry picked from commit a273032)

Author: crisbeto

src/cdk/menu/context-menu-trigger.ts

@@ -57,6 +57,7 @@ export type ContextMenuCoordinates = {x: number; y: number};
 @Directive({
   selector: '[cdkContextMenuTriggerFor]',
   exportAs: 'cdkContextMenuTriggerFor',
+  standalone: true,
   host: {
     '[attr.data-cdk-menu-stack-id]': 'null',
     '(contextmenu)': '_openOnContextMenu($event)',

src/cdk/menu/menu-aim.ts

@@ -254,6 +254,7 @@ export class TargetMenuAim implements MenuAim, OnDestroy {
 @Directive({
   selector: '[cdkTargetMenuAim]',
   exportAs: 'cdkTargetMenuAim',
+  standalone: true,
   providers: [{provide: MENU_AIM, useClass: TargetMenuAim}],
 })
 export class CdkTargetMenuAim {}

src/cdk/menu/menu-bar.ts

@@ -31,6 +31,7 @@ import {CdkMenuBase} from './menu-base';
 @Directive({
   selector: '[cdkMenuBar]',
   exportAs: 'cdkMenuBar',
+  standalone: true,
   host: {
     'role': 'menubar',
     'class': 'cdk-menu-bar',

src/cdk/menu/menu-group.ts

@@ -15,6 +15,7 @@ import {UniqueSelectionDispatcher} from '@angular/cdk/collections';
 @Directive({
   selector: '[cdkMenuGroup]',
   exportAs: 'cdkMenuGroup',
+  standalone: true,
   host: {
     'role': 'group',
     'class': 'cdk-menu-group',

src/cdk/menu/menu-item-checkbox.ts

@@ -17,6 +17,7 @@ import {CdkMenuItem} from './menu-item';
 @Directive({
   selector: '[cdkMenuItemCheckbox]',
   exportAs: 'cdkMenuItemCheckbox',
+  standalone: true,
   host: {
     'role': 'menuitemcheckbox',
     '[class.cdk-menu-item-checkbox]': 'true',

src/cdk/menu/menu-item-radio.ts

@@ -22,6 +22,7 @@ let nextId = 0;
 @Directive({
   selector: '[cdkMenuItemRadio]',
   exportAs: 'cdkMenuItemRadio',
+  standalone: true,
   host: {
     'role': 'menuitemradio',
     '[class.cdk-menu-item-radio]': 'true',

src/cdk/menu/menu-item.ts

@@ -36,6 +36,7 @@ import {MENU_AIM, Toggler} from './menu-aim';
 @Directive({
   selector: '[cdkMenuItem]',
   exportAs: 'cdkMenuItem',
+  standalone: true,
   host: {
     'role': 'menuitem',
     'class': 'cdk-menu-item',

src/cdk/menu/menu-module.ts

@@ -18,8 +18,7 @@ import {CdkMenuTrigger} from './menu-trigger';
 import {CdkContextMenuTrigger} from './context-menu-trigger';
 import {CdkTargetMenuAim} from './menu-aim';
 
-/** The list of components and directives that should be declared and exported from this module. */
-const EXPORTED_DECLARATIONS = [
+const MENU_DIRECTIVES = [
   CdkMenuBar,
   CdkMenu,
   CdkMenuItem,
@@ -33,8 +32,7 @@ const EXPORTED_DECLARATIONS = [
 
 /** Module that declares components and directives for the CDK menu. */
 @NgModule({
-  imports: [OverlayModule],
-  exports: EXPORTED_DECLARATIONS,
-  declarations: EXPORTED_DECLARATIONS,
+  imports: [OverlayModule, ...MENU_DIRECTIVES],
+  exports: MENU_DIRECTIVES,
 })
 export class CdkMenuModule {}

src/cdk/menu/menu-trigger.ts

@@ -42,6 +42,7 @@ import {CdkMenuTriggerBase, MENU_TRIGGER} from './menu-trigger-base';
 @Directive({
   selector: '[cdkMenuTriggerFor]',
   exportAs: 'cdkMenuTriggerFor',
+  standalone: true,
   host: {
     'class': 'cdk-menu-trigger',
     'aria-haspopup': 'menu',

src/cdk/menu/menu.ts

@@ -25,6 +25,7 @@ import {CdkMenuBase} from './menu-base';
 @Directive({
   selector: '[cdkMenu]',
   exportAs: 'cdkMenu',
+  standalone: true,
   host: {
     'role': 'menu',
     'class': 'cdk-menu',