Add an error message when serving the app with wrong types of the config params

[SamMethnani]

Describe the bug
Currently, there is no error message when serving the app with incorrect types of the configuration parameters. Although the app is served, it does not display the parameters in the UI.

To Reproduce
Steps to reproduce the behavior:

• config the params like this, where temperature is a float not an integer:
  ag.config.register_default( temperature=ag.IntParam(0.9, 0.0, 1.0), )
• then serve the variant
• check it in th UI

Expected behavior
When serving with incorrect types, displaying an error message informing it.

Screenshots