fix: remove duplicate AI test page header

src/main/java/com/example/workutils/biz/aitest/AiTestPane.java

@@ -101,7 +101,6 @@ public class AiTestPane extends BorderPane {
 
     private void buildUi() {
         setPadding(new Insets(20));
-        setTop(buildHeader());
         setCenter(buildContent());
         setBottom(buildStatus());
         generateButton.setDisable(true);
@@ -115,15 +114,6 @@ public class AiTestPane extends BorderPane {
         projectCombo.setButtonCell(projectCell());
     }
 
-    private Node buildHeader() {
-        Label title = new Label("AI 单测生成");
-        title.setStyle("-fx-font-size: 22px; -fx-font-weight: bold;");
-        Label subtitle = new Label("CodeFree CLI · JDK 8 · Maven · JUnit 5 · 85% 增量行覆盖率");
-        VBox header = new VBox(5, title, subtitle);
-        header.setPadding(new Insets(0, 0, 16, 0));
-        return header;
-    }
-
     private Node buildContent() {
         GridPane selection = grid();
         addRow(selection, 0, "项目", projectCombo, "生成模块", moduleCombo);

src/test/java/com/example/workutils/biz/aitest/AiTestPaneArchitectureTest.java

@@ -36,6 +36,7 @@ class AiTestPaneArchitectureTest {
     void presentsFourMainTabsWithoutAccordionAndStartsIdle() throws Exception {
         AiTestPane pane = createPane();
 
+        assertEquals(null, FxTestSupport.fx(pane::getTop));
         TabPane mainTabs = assertInstanceOf(TabPane.class, FxTestSupport.fx(pane::getCenter));
         assertEquals(List.of("项目与增量", "工具链", "质量规范", "结果与合并"),
                 FxTestSupport.fx(() -> mainTabs.getTabs().stream().map(tab -> tab.getText()).toList()));