fix: OAuth2 인증이 성공했을 때 사용자를 리다이렉트할 URL을 지정

- http://localhost:3000/oauth2/callback
로 리다이렉트할 url 지정
- 프론트에서 code(인가코드)보내는 방식으로 변경

src/main/java/com/solucitation/midpoint_backend/global/config/SecurityConfig.java

@@ -16,6 +16,8 @@
 import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
 import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.security.web.SecurityFilterChain;
+import org.springframework.security.web.authentication.AuthenticationSuccessHandler;
+import org.springframework.security.web.authentication.SimpleUrlAuthenticationSuccessHandler;
 import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
 import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.cors.CorsConfigurationSource;
@@ -91,14 +93,17 @@ public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Excepti
                 // Spring Security에서 OAuth2 로그인을 설정
                 // OAuth2 인증이 성공적으로 완료된 후 리다이렉트할 URL을 설정
                 .oauth2Login(oauth2 -> oauth2
-                        .defaultSuccessUrl("/api/auth/oauth2/code/kakao")
+                        .successHandler(oauth2AuthenticationSuccessHandler())
                 );
         // JWT 필터 추가
         http.addFilterBefore(new JwtFilter(jwtTokenProvider), UsernamePasswordAuthenticationFilter.class);
 
         return http.build();
     }
-
+    @Bean
+    public AuthenticationSuccessHandler oauth2AuthenticationSuccessHandler() {
+        return new SimpleUrlAuthenticationSuccessHandler("http://localhost:3000/oauth2/callback");
+    }
 
     /**
      * CORS 설정 빈 등록