OZG-1194 show attachment icon on vorgang detail

goofy-client/libs/postfach/src/lib/postfach-mail-list-container/postfach-mail-list/postfach-mail/postfach-mail.component.html

 <goofy-client-incomming-mail *ngIf="isIncomingMail" [postfachMail]="postfachMail"></goofy-client-incomming-mail>
 <goofy-client-outgoing-mail *ngIf="!isIncomingMail" [postfachMail]="postfachMail"></goofy-client-outgoing-mail>
 
-<ng-container *ngIf="onPage">
+<ng-container *ngIf="onPage; else icon">
 	<goofy-client-postfach-nachricht-attachments *ngIf="postfachMail | hasLink: postfachNachrichtLinkRel.ATTACHMENTS" data-test-id="postfach-nachricht-attachments-container"
 		[postfachNachricht]="postfachMail">
 	</goofy-client-postfach-nachricht-attachments>
 </ng-container>
+<ng-template #icon>
+	<mat-icon data-test-id="postfach-nachricht-attachment-icon">attach_file</mat-icon>
+</ng-template>
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goofy-client/libs/postfach/src/lib/postfach-mail-list-container/postfach-mail-list/postfach-mail/postfach-mail.component.spec.ts

 import { ComponentFixture, TestBed } from '@angular/core/testing';
+import { MatIcon } from '@angular/material/icon';
 import { ON_PAGE, PostfachMailLinkRel } from '@goofy-client/postfach-shared';
 import { HasLinkPipe } from '@goofy-client/tech-shared';
 import { getElementFromFixture } from '@goofy-client/test-utils';
@@ -14,12 +15,14 @@ describe('PostfachMailComponent', () => {
 	let fixture: ComponentFixture<PostfachMailComponent>;
 
 	const attachmentContainer: string = '[data-test-id="postfach-nachricht-attachments-container"]';
+	const attachmentIcon: string = '[data-test-id="postfach-nachricht-attachment-icon"]';
 
 	beforeEach(async () => {
 		await TestBed.configureTestingModule({
 			declarations: [
 				PostfachMailComponent,
 				HasLinkPipe,
+				MatIcon,
 				MockComponent(IncommingMailComponent),
 				MockComponent(OutgoingMailComponent),
 				MockComponent(PostfachNachrichtAttachmentsComponent)
@@ -27,7 +30,7 @@ describe('PostfachMailComponent', () => {
 			providers: [
 				{
 					provide: ON_PAGE,
-					useValue: true
+					useValue: undefined
 				}
 			]
 		}).compileComponents();
@@ -47,6 +50,7 @@ describe('PostfachMailComponent', () => {
 	describe('attachments', () => {
 
 		it('should not show attachments loaded if exists', () => {
+			component.onPage = true;
 			component.postfachMail = createPostfachMailResource();
 			fixture.detectChanges();
 
@@ -56,6 +60,7 @@ describe('PostfachMailComponent', () => {
 		})
 
 		it('should be loaded if exists', () => {
+			component.onPage = true;
 			component.postfachMail = createPostfachMailResource([PostfachMailLinkRel.ATTACHMENTS]);
 			fixture.detectChanges();
 
@@ -63,5 +68,14 @@ describe('PostfachMailComponent', () => {
 
 			expect(element).toBeInstanceOf(HTMLElement);
 		})
+
+		it('should only show attachment icon on detail', () => {
+			component.onPage = false;
+			fixture.detectChanges();
+
+			const element = getElementFromFixture(fixture, attachmentIcon);
+
+			expect(element).toBeInstanceOf(HTMLElement);
+		})
 	})
 });
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