세션 IP 표시와 로그아웃 처리 보강

backend/internal/middleware/audit_middleware_test.go

@@ -117,6 +117,30 @@ func TestAuditMiddleware(t *testing.T) {
 		mockRepo.AssertExpectations(t)
 	})
 
+	t.Run("POST request - Prefer public forwarded IP", func(t *testing.T) {
+		app := fiber.New()
+		mockRepo := new(MockAuditRepository)
+
+		app.Use(AuditMiddleware(AuditConfig{
+			Repo: mockRepo,
+		}))
+
+		app.Post("/test", func(c *fiber.Ctx) error {
+			return c.SendStatus(fiber.StatusOK)
+		})
+
+		mockRepo.On("Create", mock.MatchedBy(func(log *domain.AuditLog) bool {
+			return log.IPAddress == "203.0.113.25"
+		})).Return(nil)
+
+		req := httptest.NewRequest("POST", "/test", nil)
+		req.Header.Set("X-Forwarded-For", "100.100.100.1, 203.0.113.25")
+
+		resp, _ := app.Test(req)
+		assert.Equal(t, fiber.StatusOK, resp.StatusCode)
+		mockRepo.AssertExpectations(t)
+	})
+
 	t.Run("POST request - Sync Failure (Strict Mode)", func(t *testing.T) {
 		app := fiber.New()
 		mockRepo := new(MockAuditRepository)