Replace deprecated Angular directives (*ngFor, *ngIf) with modern Angular template syntax. Remove unused CommonModule imports across components for optimization. Clean up excess spacing and formatting in HTML files.

frontend/src/app/pages/altitude/birthdays/birthdays.component.ts

@@ -1,15 +1,14 @@
 import {Component} from '@angular/core';
 import {ScrollService} from '@services/scroll.service';
-import {CommonModule} from '@angular/common';
+
 import {HeaderComponent} from '@header/header.component';
 
 @Component({
   selector: 'app-birthdays',
   standalone: true,
   imports: [
-    CommonModule,
     HeaderComponent
-  ],
+],
   templateUrl: './birthdays.component.html',
   styleUrl: './birthdays.component.scss'
 })