Feature/save signs (#2127)

* apply fix

* Fixes empty th:action

* Update build.gradle

* fix

* formatting

* Save signatures

* Fix code scanning alert no. 42: Uncontrolled data used in path expression

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

* fix UserServiceInterface

* Merge branch 'feature/saveSigns' of
git@github.com:Stirling-Tools/Stirling-PDF.git into feature/saveSigns

* 0.31.0 bump and further csrf

* formatting

* preview name

* add

* sign doc

* Update translation files (#2128)

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---------

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Co-authored-by: Dimitrios Kaitantzidis <james_k23@hotmail.gr>
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Co-authored-by: a <a>
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src/main/resources/templates/misc/compress-pdf.html

@@ -20,6 +20,7 @@
               <span class="tool-header-text" th:text="#{compress.header}"></span>
             </div>
             <form action="#" th:action="@{'/api/v1/misc/compress-pdf'}" method="post" enctype="multipart/form-data">
+             <input type="hidden" th:name="${_csrf.parameterName}" th:value="${_csrf.token}" />
               <div
                 th:replace="~{fragments/common :: fileSelector(name='fileInput', multipleInputsForSingleRequest=false, accept='application/pdf')}">
               </div>