fix: Fixed book title in home screen (#1013)

## Summary

* **What is the goal of this PR?** (e.g., Implements the new feature for
file uploading.)
* The goal is to fix the title of books in the Home Screen. 

Before

![IMG_8867](https://github.com/user-attachments/assets/6cc9ca22-b95b-4863-872d-ef427c42f833)

After:

![IMG_8868](https://github.com/user-attachments/assets/585031b1-2348-444c-8f32-073fed3b6582)

* **What changes are included?**

## Additional Context

* Add any other information that might be helpful for the reviewer
(e.g., performance implications, potential risks,
  specific areas to focus on).

---

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lib/Epub/Epub/parsers/ContentOpfParser.cpp

@@ -102,7 +102,10 @@ void XMLCALL ContentOpfParser::startElement(void* userData, const XML_Char* name
   }
 
   if (self->state == IN_METADATA && strcmp(name, "dc:title") == 0) {
-    self->state = IN_BOOK_TITLE;
+    // Only capture the first dc:title element; subsequent ones are subtitles
+    if (self->title.empty()) {
+      self->state = IN_BOOK_TITLE;
+    }
     return;
   }