Refactor avatar URL generation into reusable method

Centralized avatar URL generation with `getAvatarUrl()` method to reduce redundancy and improve code maintainability. Updated relevant components to utilize the new method for cleaner and more consistent implementation.

frontend/src/app/bans/history/history.component.ts

@@ -89,4 +89,9 @@ export class HistoryComponent implements OnInit, OnChanges {
       hour12: false
     });
   }
+
+  public getAvatarUrl(entry: PunishmentHistoryInner): string {
+    let uuid = entry.uuid.replace('-', '');
+    return `https://crafatar.com/avatars/${uuid}?size=25&overlay`;
+  }
 }