Make chatbot text input expand when newline is encountered instead of single line only

[mturoci]

Is your feature request related to a problem? Please describe

The current chatbot card input textbox accepts a single line text only, which is not enough.

Describe the solution you'd like

The textbox should grow in height as needed (depending on the amount of newlines) and maxing out on a specified threshold. Same as other popular chatbots work.