test(shopping): add HTTP-level role guard test and blank customName validation test

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/test/java/com/recipeapp/shopping/ShoppingListControllerTest.java

@@ -3,8 +3,10 @@ package com.recipeapp.shopping;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
 import com.recipeapp.common.GlobalExceptionHandler;
+import com.recipeapp.common.HouseholdRoleInterceptor;
 import com.recipeapp.recipe.HouseholdResolver;
 import com.recipeapp.shopping.dto.*;
+import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
@@ -12,6 +14,8 @@ import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.http.MediaType;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.context.SecurityContextHolder;
 import org.springframework.test.web.servlet.MockMvc;
 import org.springframework.test.web.servlet.setup.MockMvcBuilders;
 
@@ -49,6 +53,11 @@ class ShoppingListControllerTest {
                 .build();
     }
 
+    @AfterEach
+    void clearSecurityContext() {
+        SecurityContextHolder.clearContext();
+    }
+
     @Test
     void getByWeekStartShouldReturn200() throws Exception {
         var response = new ShoppingListResponse(LIST_ID, PLAN_ID, Instant.now(), 3, List.of());
@@ -169,4 +178,20 @@ class ShoppingListControllerTest {
                                 new AddItemRequest(null, "  ", new BigDecimal("1"), ""))))
                 .andExpect(status().isBadRequest());
     }
+
+    @Test
+    void generateFromPlanShouldReturn403ForNonPlanner() throws Exception {
+        SecurityContextHolder.getContext().setAuthentication(
+                new UsernamePasswordAuthenticationToken("member@example.com", null));
+        when(householdResolver.resolveRole("member@example.com")).thenReturn("member");
+
+        MockMvc mockMvcWithInterceptor = MockMvcBuilders.standaloneSetup(shoppingListController)
+                .setControllerAdvice(new GlobalExceptionHandler())
+                .addInterceptors(new HouseholdRoleInterceptor(householdResolver))
+                .build();
+
+        mockMvcWithInterceptor.perform(post("/v1/week-plans/{id}/shopping-list", PLAN_ID)
+                        .principal(() -> "member@example.com"))
+                .andExpect(status().isForbidden());
+    }
 }