Is your feature request related to a problem? Please describe.
Auto-switch mode is useful for users who install the mod and clearly know when and how to use it. However, it is not that ideal for modpacks, where there may be people who have a controller attached but don't expect it to do anything in this game.

Describe the solution you'd like
A default-disabled option that shows a toast when:

• the player joins any world
• no other toasts are currently shown
• the player has a controller/touchscreen attached
• the control mode is set to something other than "keyboard/mouse"
• the player has not already seen the toast (displayed once)

The toast would say something like:

ControllerName detected
To use, switch mode on Controls... -> Controller Options...

Describe alternatives you've considered
The single-use toast can be replaced with:

• a prompt asking to use the new control method
• a toast that appears on every game launch

but these could become annoying, so it needs to be thought over.

Or the modpack could just disable auto-switch and advertise it in some other way.

Additional context
The suggestion is inspired by my modpack users who reported weird spinning and button swaps, without knowing that their controller could be the cause because they didn't expect it.