Remove book (#3065)

# Description of Changes

Please provide a summary of the changes, including:

- What was changed
- Why the change was made
- Any challenges encountered

Closes #(issue_number)

---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] 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)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing)
for more details.

build.gradle

@@ -25,7 +25,7 @@ ext {
 }
 
 group = "stirling.software"
-version = "0.43.0"
+version = "0.43.1"
 
 java {
     // 17 is lowest but we support and recommend 21

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

@@ -59,9 +59,6 @@
       <div
         th:replace="~{fragments/navbarEntry :: navbarEntry('markdown-to-pdf', 'markdown', 'home.MarkdownToPDF.title', 'home.MarkdownToPDF.desc', 'MarkdownToPDF.tags', 'convertto')}">
       </div>
-      <div
-        th:replace="~{fragments/navbarEntry :: navbarEntry('book-to-pdf', 'book', 'home.BookToPDF.title', 'home.BookToPDF.desc', 'BookToPDF.tags', 'convertto')}">
-      </div>
     </div>
   </div>
   <div id="groupConvertFrom" class="feature-group">
@@ -92,9 +89,6 @@
       <div
         th:replace="~{fragments/navbarEntry :: navbarEntry('pdf-to-csv', 'csv', 'home.tableExtraxt.title', 'home.tableExtraxt.desc', 'tableExtraxt.tags', 'convert')}">
       </div>
-      <div
-        th:replace="~{fragments/navbarEntry :: navbarEntry('pdf-to-book', 'book', 'home.PDFToBook.title', 'home.PDFToBook.desc', 'PDFToBook.tags', 'convert')}">
-      </div>
       <div
         th:replace="~{fragments/navbarEntry :: navbarEntry ('pdf-to-markdown', 'markdown_copy', 'home.PDFToMarkdown.title', 'home.PDFToMarkdown.desc', 'PDFToMarkdown.tags', 'convert')}">
       </div>
@@ -120,9 +114,6 @@
       <div
         th:replace="~{fragments/navbarEntry :: navbarEntry('markdown-to-pdf', 'markdown', 'home.MarkdownToPDF.title', 'home.MarkdownToPDF.desc', 'MarkdownToPDF.tags', 'convertto')}">
       </div>
-      <div
-        th:replace="~{fragments/navbarEntry :: navbarEntry('book-to-pdf', 'book', 'home.BookToPDF.title', 'home.BookToPDF.desc', 'BookToPDF.tags', 'convertto')}">
-      </div>
     </div>
     <div th:replace="~{fragments/featureGroupHeader :: featureGroupHeader(groupTitle=#{navbar.sections.convertFrom})}">
     </div>
@@ -151,9 +142,6 @@
       <div
         th:replace="~{fragments/navbarEntry :: navbarEntry('pdf-to-csv', 'csv', 'home.tableExtraxt.title', 'home.tableExtraxt.desc', 'tableExtraxt.tags', 'convert')}">
       </div>
-      <div
-        th:replace="~{fragments/navbarEntry :: navbarEntry('pdf-to-book', 'book', 'home.PDFToBook.title', 'home.PDFToBook.desc', 'PDFToBook.tags', 'convert')}">
-      </div>
     </div>
   </div>
   <div id="groupSecurity" class="feature-group">

src/main/resources/templates/home-legacy.html

@@ -163,9 +163,6 @@
               <div
                 th:replace="~{fragments/card :: card(id='markdown-to-pdf', cardTitle=#{home.MarkdownToPDF.title}, cardText=#{home.MarkdownToPDF.desc}, cardLink='markdown-to-pdf', toolIcon='markdown', tags=#{MarkdownToPDF.tags}, toolGroup='convert')}">
               </div>
-              <div
-                th:replace="~{fragments/card :: card(id='book-to-pdf', cardTitle=#{home.BookToPDF.title}, cardText=#{home.BookToPDF.desc}, cardLink='book-to-pdf', toolIcon='book', tags=#{BookToPDF.tags}, toolGroup='convert')}">
-              </div>
             </div>
           </div>
 
@@ -198,9 +195,6 @@
               <div
                 th:replace="~{fragments/card :: card(id='pdf-to-csv', cardTitle=#{home.tableExtraxt.title}, cardText=#{home.tableExtraxt.desc}, cardLink='pdf-to-csv', toolIcon='csv', tags=#{tableExtraxt.tags}, toolGroup='convert')}">
               </div>
-              <div
-                th:replace="~{fragments/card :: card(id='pdf-to-book', cardTitle=#{home.PDFToBook.title}, cardText=#{home.PDFToBook.desc}, cardLink='pdf-to-book', toolIcon='book', tags=#{PDFToBook.tags}, toolGroup='convert')}">
-              </div>
             </div>
           </div>