Update to Gradio 6.x API

- Move css from gr.Blocks() to launch()
- Replace show_api with footer_links parameter
- Remove theme from Blocks (moved to launch in Gradio 6)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

main.py

@@ -126,11 +126,13 @@ def main():
     # Launch the app
     logger.info("Launching application...")
     try:
+        # Gradio 6.x: show_api replaced with footer_links
+        footer = ["api", "gradio"] if settings.api_enabled else ["gradio"]
         app.launch(
             server_name=settings.host,
             server_port=settings.gradio_port,
             share=False,
-            show_api=settings.api_enabled,
+            footer_links=footer,
         )
     except KeyboardInterrupt:
         logger.info("Shutting down...")