Set input limits for Form widget

### Description

Hi,
I need to check (text,number...) input from dashboard users for correctness and syntax. One basic check is the length of the input value(s). I'm using the form widget for this, but it might also be great for the simple text input widget to implement a character limit.
Specifically I'm thinking of a optional value here that is set to a number which indicates how long the input for the form element needs to be. The form can only be submitted when the length is correct.

User could be notified of this, the same way the "required" value is displayed:
E.g. "SMSP/SRQP needs to be X characters long"

Thanks a lot! If anything is unclear, pls just let me know.

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate