fix: close final portfolio quality gaps

tests/unit/navigation-controller.test.ts

@@ -152,6 +152,25 @@ describe("canonical fragment validation", () => {
     anchor.href = "#unknown";
     expect(validateSectionAnchor(anchor, sectionIds)).toBeNull();
   });
+
+  it("validates the nested hero H1 as the Start navigation target", () => {
+    const section = document.createElement("section");
+    section.id = "start";
+    const content = document.createElement("div");
+    const heading = document.createElement("h1");
+    heading.id = "start-heading";
+    heading.tabIndex = -1;
+    content.append(heading);
+    section.append(content);
+    const anchor = document.createElement("a");
+    anchor.href = "#start";
+    document.body.append(section, anchor);
+
+    expect(validateSectionAnchor(anchor, sectionIds)).toEqual({
+      id: "start",
+      target: section,
+    });
+  });
 });
 
 describe("navigation epochs and effects", () => {