GitLab

- Implement to_pdf function to convert non-PDF files to PDF format
- Integrate file upload functionality for PDF and image files- Update UI to include file upload component and PDF preview
- Add conversion button and update its functionality to handle new file types

- Add new layout model option: DocLayout-YOLO
- Implement model initialization and prediction for DocLayout-YOLO
- Update configuration options to include new model- Modify existing code to support both LayoutLMv3 and DocLayout-YOLO models
- Update Gradio app to support more Custom Switch

Introduce an examples accordion within the Gradio application to provide users with
a selection of sample PDFs for demonstration purposes. The added functionality allows
users to quickly test the PDF conversion feature with various document types.

Removed the previously used gradio and gradio-pdf imports which were not leveraged in the code. Also,
replaced the custom `show_pdf` function with direct use of the `PDF` component from gradio for a simpler
and more integrated PDF upload and display solution, improving code maintainability and readability.