Add disconnection and minor improvements on login page.

frontend/src/app/core/service/authentication.service.ts

@@ -55,7 +55,8 @@ export class AuthenticationService {
 
         const tokenParts = token?.split('.');
         if (tokenParts?.length === 3 && tokenParts[1].length) {
-            const userDetails: UserDetails = JSON.parse(tokenParts[1]);
+            const decodedTokenPart = atob(tokenParts[1]);
+            const userDetails: UserDetails = JSON.parse(decodedTokenPart);
             result = userDetails;
         }