Unit-specific hotkey UI uses wrong defaults

[ribbanya]

If a hero's key is unbound, it uses the stock defaults, not the user's defaults.

1. Change a default keybind, such as Forward from W to Q.
2. Select a hero with no specific keybinds set.
3. In the UI, Forward will be W (the stock default), but in-game pressing Q will move the character forward.
4. Overriding the hero's bind for Forward will work correctly in the UI and in-game.

 

[ribbanya]

Actually it seems like the unit-specific binds will always layer on top of the stock defaults, if the hero has an entry in citadelkeys_personal. They should layer on top of the user's defaults.

 

[ribbanya]

Related to #29332.