style: Consistent backdrop and create server in server-rail

wider server rail with larger icons ans slightly animated.

toju-app/src/app/domains/direct-call/feature/incoming-call-modal/incoming-call-modal.component.html

@@ -1,5 +1,5 @@
 @if (session()) {
-  <div class="fixed inset-0 z-[120] bg-black/60 backdrop-blur-sm"></div>
+  <app-modal-backdrop [zIndex]="120" [dismissable]="false" />
 
   <div class="pointer-events-none fixed inset-0 z-[121] flex items-center justify-center p-4">
     <section

toju-app/src/app/domains/direct-call/feature/incoming-call-modal/incoming-call-modal.component.ts

@@ -9,7 +9,7 @@ import { CommonModule } from '@angular/common';
 import { Store } from '@ngrx/store';
 import { NgIcon, provideIcons } from '@ng-icons/core';
 import { lucidePhone, lucidePhoneOff } from '@ng-icons/lucide';
-import { UserAvatarComponent } from '../../../../shared';
+import { ModalBackdropComponent, UserAvatarComponent } from '../../../../shared';
 import { selectCurrentUser } from '../../../../store/users/users.selectors';
 import { User } from '../../../../shared-kernel';
 import { DirectCallService } from '../../application/services/direct-call.service';
@@ -21,7 +21,8 @@ import { DirectCallSession, participantToUser } from '../../domain/models/direct
   imports: [
     CommonModule,
     NgIcon,
-    UserAvatarComponent
+    UserAvatarComponent,
+    ModalBackdropComponent
   ],
   viewProviders: [
     provideIcons({