Add DiscordAppealMapper to initialization and simplify username reload logic in auth service.

frontend/src/app/services/auth.service.ts

@@ -87,9 +87,7 @@ export class AuthService {
       const claims = this.extractJwtClaims(jwt);
       this.userClaimsSubject.set(claims);
       this.isAuthenticatedSubject.set(true);
-      if (this.username() == null) {
-        this.reloadUsername();
-      }
+      this.reloadUsername();
       return true;
     } catch (e) {
       this.logout();