feat: added most of shared API calls

MyINPulse-back/src/main/java/enseirb/myinpulse/service/database/UserService.java

@@ -26,15 +26,14 @@ public class UserService {
     }
 
     // TODO
-    public long getIdUserByEmail(String email) {
+    public User getUserByEmail(String email) {
         Optional<User> opt_user = this.userRepository.findByPrimaryMail(email);
 
         if (opt_user.isEmpty()) {
             System.err.println("Couldn't find user with email " + email);
             throw new ResponseStatusException(HttpStatus.NOT_FOUND);
         }
-        User user = opt_user.get();
-        return user.getIdUser();
+        return opt_user.get();
     }
 
     public Iterable<User> allUsers() {