Edit float atom, symbol atom, and IEM numbers with keyboard

[danomatika]

Add ability to edit float atom, symbol atom, and IEM numbers using the keyboard to edit string directly, similar to desktop Pd.

This could be done using a long press or double tap on the widget which then shows the system keyboard. It should also handle the case where a USB or Bluetooth keyboard is connected, ie. allow edit without on screen keyboard.

Suggested by @Josef-N

[Josef-N]

great!