Updating and correcting i18n strings

frontend/src/app/components/calculator/calculator.component.html

@@ -1,6 +1,6 @@
 <div class="container-xl">
   <div class="text-center">
-    <h2>Calculator</h2>
+    <h2 i18n="shared.calculator">Calculator</h2>
   </div>
 
   <ng-container *ngIf="price$ | async; else loading">