feat(security): add CORS support and update security config

frontend/src/app/service/user.service.ts

@@ -1,6 +1,6 @@
 import { inject, Injectable } from '@angular/core';
 import { HttpClient } from '@angular/common/http';
-import { catchError, EMPTY, Observable, of, switchMap } from 'rxjs';
+import { catchError, EMPTY, Observable } from 'rxjs';
 import { User } from '../model/User';
 
 @Injectable({
@@ -9,10 +9,6 @@ import { User } from '../model/User';
 export class UserService {
   private http: HttpClient = inject(HttpClient);
 
-  public getUser(id: string): Observable<User | null> {
-    return this.http.get<User | null>(`/backend/user/${id}`).pipe(catchError(() => EMPTY));
-  }
-
   public getCurrentUser(): Observable<User | null> {
     return this.http.get<User | null>('/backend/user').pipe(catchError(() => EMPTY));
   }
@@ -27,10 +23,6 @@ export class UserService {
   public getOrCreateUser(profile: any): Observable<User> {
     const id = profile.info.sub;
     const username = profile.info.preferred_username;
-    try {
-      return this.getUser(id) as Observable<User>;
-    } catch (error) {
-      return this.createUser(id, username);
-    }
+    return this.createUser(id, username);
   }
 }