csrf fixes (#2647)

# Description

Please provide a summary of the changes, including relevant motivation
and context.

Closes #(issue_number)

## Checklist

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have performed a self-review of my own code
- [ ] I have attached images of the change if it is UI based
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] If my code has heavily changed functionality I have updated
relevant docs on [Stirling-PDFs doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
- [ ] My changes generate no new warnings
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

src/main/resources/templates/fragments/common.html

@@ -73,6 +73,7 @@
     <script th:src="@{'/js/cacheFormInputs.js'}"  th:if="${currentPage != 'home'}"></script>
     <script th:src="@{'/js/tab-container.js'}"></script>
     <script th:src="@{'/js/darkmode.js'}"></script>
+    <script th:src="@{'/js/csrf.js'}"></script>
     <script th:inline="javascript">
         const stirlingPDFLabel = /*[[${@StirlingPDFLabel}]]*/ '';
         const analyticsEnabled = /*[[${@analyticsEnabled}]]*/ false;