feat: update README with Overleaf Pro features and add new screenshot

Author: Musicminion

README.md

@@ -14,11 +14,29 @@
   <a href="#license">License</a>
 </p>
 
-<img src="doc/screenshot.png" alt="A screenshot of a project being edited in Overleaf Community Edition">
+<img src="doc/screenshot-pro.png" alt="A screenshot of a project being edited in Overleaf Community Edition">
 <p align="center">
-  Figure 1: A screenshot of a project being edited in Overleaf Community Edition.
+  Figure 1: A screenshot of a project being edited in Overleaf Pro Edition.
 </p>
 
+## Overleaf Pro Edition
+Overleaf Pro is an enhanced version of Overleaf with almost all features and capabilities. For details, please check [Overleaf Pro](https://overleaf-pro.ayaka.space) page. Features in Overleaf Pro include: 
+
+- GitHub Sync in 2-ways (Features in SaaS)
+- Git-Bridge Support (Features in Server Pro)
+- Admin Panel (User/Project management)
+- SSO with LDAP and SAML or OAuth 2.0
+- Unlimited Compile Times (Adjustable in admin panel)
+- Self Register (Optional, can be limited by mail domain)
+- Sandbox Compile (With [texlive-full](https://github.com/ayaka-notes/texlive-full) Image Support)
+- Template System (With Template Gallery)
+- Track Changes (With Review and Comment Panel)
+- Full Project History
+- Symbol Palette
+- ARM Support
+
+Last but not least, Overleaf Pro is open-source, free to use and modify. You can self-host it and contribute to the development of Overleaf Pro. For more details, please check [Developer Documentation](https://overleaf-pro.ayaka.space/dev) page.
+
 ## Community Edition
 
 [Overleaf](https://www.overleaf.com) is an open-source online real-time collaborative LaTeX editor. We run a hosted version at [www.overleaf.com](https://www.overleaf.com), but you can also run your own local version, and contribute to the development of Overleaf.