feat: allow-none-key-name

[Yujonpradhananga]

Summary:

This PR implements true modifier-only keybindings (e.g., bindr=SUPER,none,toggleovervie).
It allows an action to fire when a modifier key is released, but only if no other key was pressed during the hold.
Introduces mod_key_used and prev_mods to track state. If you press SUPER+R to reload, the solo SUPER release won't accidentally trigger a "none" binding.
The config parser now recognizes the "none" key. It also includes safety logic that automatically forces release mode (bindr) for these bindings and issues a warning if the user accidentally uses the standard

Closes #689

[demperor-music]

The none keybinds seem to trigger if trying to activate a shortcut involving an additional modifier.
Example: Super,none,toggleoverview activates when pressing SUPER+SHIFT if you start the chord by pressing SUPER rather than SHIFT

[Yujonpradhananga]

Oh my bad, I fixed the bug in f0fe874, now it should work as intended @demperor-music

[mariokhz]

thank you!!!

[mariokhz]

if you are using bind=SUPER,none, doing SUPER+CLICK to move a window will activate the bind once SUPER is released

[Yujonpradhananga]

Oh I didnt think about the mouse click behaviour at all as I have never used it , but I've added the fix at 6236adb
I've squashed the commits too for better readability
could you try it out @mariokhz @demperor-music

[Yujonpradhananga]

@DreamMaoMao Can this be merged Maomao?

[demperor-music]

The fix works just fine on my machine