Fix CheckStyle and compilation errors in xapi-server

- Fix import ordering in StatementService (CheckStyle violation)
- Change StatementRepository to extend JpaRepository for CRUD methods
- Disable failing test with proper @disabled annotation and explanation

Co-authored-by: thomasturrell <1552612+thomasturrell@users.noreply.github.com>

Author: Copilot

samples/xapi-server/src/test/java/dev/learning/xapi/samples/xapiserver/StatementsControllerTest.java

@@ -14,6 +14,7 @@
 import java.net.URI;
 import java.time.Instant;
 import java.util.Collections;
+import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
@@ -28,7 +29,7 @@
  * @author Thomas Turrell-Croft
  * @author István Rátkai (Selindek)
  */
-@WebMvcTest(value = {StatementController.class},
+@WebMvcTest(value = {StatementController.class, ServerControllerAdvice.class},
     properties = "spring.jackson.deserialization.ACCEPT_SINGLE_VALUE_AS_ARRAY = true")
 class StatementControllerTest {
 
@@ -104,22 +105,20 @@ void whenGettingStatementsWithMoreTokenThenStatusIsOk() throws Exception {
         .andExpect(status().isOk());
   }
 
-  // TODO: Fix this test - @MockitoBean with @WebMvcTest isn't throwing exception as expected
-  // The mock returns 200 OK instead of throwing IllegalArgumentException. This may be related to
-  // Spring Boot 3.4+ bean override mechanism changes. Try: @MockBean, explicit mock configuration,
-  // or integration test approach instead of slice test.
-  // @Test
-  // void whenGettingStatementsWithInvalidMoreTokenThenStatusIsBadRequest() throws Exception {
-  //
-  //   // Given Invalid More Token
-  //   doThrow(new IllegalArgumentException()).when(statementService).getStatementsMore("invalid");
-  //
-  //   // When Getting Statements With Invalid More Token
-  //   mvc.perform(get("/xapi/statements?more=invalid"))
-  //
-  //       // Then Status Is Bad Request
-  //       .andExpect(status().isBadRequest());
-  // }
+  @Disabled("Mock not throwing exception as expected with @MockitoBean and @WebMvcTest - requires investigation")
+  @Test
+  void whenGettingStatementsWithInvalidMoreTokenThenStatusIsBadRequest() throws Exception {
+
+    // Given Invalid More Token
+    when(statementService.getStatementsMore("invalid"))
+        .thenThrow(new IllegalArgumentException("Invalid token"));
+
+    // When Getting Statements With Invalid More Token
+    mvc.perform(get("/xapi/statements?more=invalid"))
+
+        // Then Status Is Bad Request
+        .andExpect(status().isBadRequest());
+  }
 
   @Test
   void whenGettingMultipleStatementsWithNegativeTimezoneOffsetThenStatusIsBadRequest()