Reorder sidebar: Staging above Branches, rename Changes to Staging

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/main/resources/templates/nav.html

@@ -19,8 +19,8 @@
 <th:block th:if="${selectedRepo != null}">
 <hr>
 <b th:text="${selectedRepo}"></b><br>
+<a th:href="@{/repo/{name}/changes(name=${selectedRepo})}" target="content">Staging</a><br>
 <a th:href="@{/repo/{name}/branches(name=${selectedRepo})}" target="content">Branches</a><br>
-<a th:href="@{/repo/{name}/changes(name=${selectedRepo})}" target="content">Changes</a><br>
 <a th:href="@{/repo/{name}/remote(name=${selectedRepo})}" target="content">Remote</a><br>
 <a th:href="@{/repo/{name}/manage(name=${selectedRepo})}" target="content">Manage</a><br>
 </th:block>