Description of the new feature/enhancement

In the documentation at https://docs.microsoft.com/en-us/windows/terminal/customize-settings/actions#accepted-modifiers-and-keys the listed keys are:

Type | Keys
-- | --
Function and alphanumeric keys | f1-f24, a-z, 0-9
Symbols | `, plus, -, =, [, ], \, ;, ', ,, ., /
Arrow keys | down, left, right, up, pagedown, pageup, pgdn, pgup, end, home
Action keys | tab, enter, esc, escape, space, backspace, delete, insert, app, menu
Numpad keys | numpad_0-numpad_9, numpad0-numpad9, numpad_add, numpad_plus, numpad_decimal, numpad_period, numpad_divide, numpad_minus, numpad_subtract, numpad_multiply

The Back, Forward, and other multimedia keys are not mentioned. I have a TEX Shinobi and would like to bind the "Back" and "Forward" keys to previous/next tab. I had this working 10 years ago in gnome-terminal; would be nice to have this on Windows by now. :)

The nice thing about being able to use Back and Forward specifically for this is because those keys are already useful in web browsers to do what you would expect, so I don't have to write an AutoHotkey macro or rebind the behavior of the keys at the hardware level to get this working in both Terminal and on the web.

Proposed technical implementation details (optional)

Not sure exactly, but I believe the multimedia keys have normal key codes, at least on Windows. PassMark KeyboardTest reports "Windows Key Code" 0xA6 (decimal 166) for Back and 0xA7 / decimal 167 for Forward. Not sure if they are handled the same way as other keys, since no "BIOS Key Code" gets sent. I've always suspected something was a little weird / non-standard about multimedia keys.