...that is, to permanently change the current tool, and keep the current selection (which rules out SHIFT which changes it temporarily; and multiple ESC key presses which loses the current selection)?
I've looked at the Design > Design Tools menu - to see if I can assign a keystroke - but it's the only tool not listed.
There is a shortcut for arrow tool/last tool toggle.
As to what it is standrad I can not tell you.
We have this mapped to the thumb (side) button of my mouse!
I honestly cant imagine drawing without it anymore!
From Work Environment dialogue hit the "Show shortcut list in browser" button and get this and lots of other shortcuts you probably didn't even know existed.
Why would anyone bother to waste keystrokes engaging the arrow tool for selections once they know that the shift key temporarily toggles between the arrow selection tool and the current tool?