Enable verbose app errors and add private model access support

app.py

@@ -409,4 +409,4 @@ Use the structured fields if you have them. Missing fields are allowed, but spec
 
 
 if __name__ == "__main__":
-    demo.queue(default_concurrency_limit=4).launch()
+    demo.queue(default_concurrency_limit=4).launch(show_error=True)