Pdf to markdown (#2730)

# 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)

---------

Co-authored-by: a <a>

src/main/java/stirling/software/SPDF/config/EndpointConfiguration.java

@@ -126,6 +126,7 @@ public class EndpointConfiguration {
         addEndpointToGroup("Convert", "url-to-pdf");
         addEndpointToGroup("Convert", "markdown-to-pdf");
         addEndpointToGroup("Convert", "pdf-to-csv");
+        addEndpointToGroup("Convert", "pdf-to-markdown");
 
         // Adding endpoints to "Security" group
         addEndpointToGroup("Security", "add-password");
@@ -243,6 +244,7 @@ public class EndpointConfiguration {
         addEndpointToGroup("Java", REMOVE_BLANKS);
         addEndpointToGroup("Java", "pdf-to-text");
         addEndpointToGroup("Java", "remove-image-pdf");
+        addEndpointToGroup("Java", "pdf-to-markdown");
 
         // Javascript
         addEndpointToGroup("Javascript", "pdf-organizer");
@@ -258,9 +260,11 @@ public class EndpointConfiguration {
         // Weasyprint dependent endpoints
         addEndpointToGroup("Weasyprint", "html-to-pdf");
         addEndpointToGroup("Weasyprint", "url-to-pdf");
+        addEndpointToGroup("Weasyprint", "markdown-to-pdf");
 
         // Pdftohtml dependent endpoints
         addEndpointToGroup("Pdftohtml", "pdf-to-html");
+        addEndpointToGroup("Pdftohtml", "pdf-to-markdown");
 
         // disabled for now while we resolve issues
         disableEndpoint("pdf-to-pdfa");