fix(test): delete user_game_playtime_day rows in seed

RewardControllerTest leaves user_game_playtime_day rows for user 1,
affecting paceWeeks calculation. Delete them in seed() to ensure
clean test isolation.

src/test/java/core_service/modules/library/api/LibraryControllerStatsTest.java

@@ -15,6 +15,7 @@ import org.springframework.dao.DataIntegrityViolationException;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.springframework.boot.test.system.CapturedOutput;
 import org.springframework.boot.test.system.OutputCaptureExtension;
+import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.http.converter.HttpMessageNotWritableException;
 import org.springframework.boot.webmvc.test.autoconfigure.AutoConfigureMockMvc;
 import org.springframework.test.web.servlet.MockMvc;
@@ -55,9 +56,13 @@ class LibraryControllerStatsTest extends AbstractMockedLibraryServicesTest {
     @Autowired
     private GameTimeToBeatRepository gameTimeToBeatRepository;
 
+    @Autowired
+    private JdbcTemplate jdbc;
+
     @BeforeEach
     void seed() {
         userGameRepository.deleteAll();
+        jdbc.update("delete from user_game_playtime_day where user_id = ?", USER_ID);
         steamGameRepository.saveAll(List.of(
                 new SteamGame(220L, "Half-Life 2", null, Instant.now()),
                 new SteamGame(620L, "Portal 2", null, Instant.now())));