Shift-Click Damage Buttons for Modifier Popup

[Khunkurisu]

Is your feature request related to a problem? Please describe.
There are instances where damage was rolled incorrectly or should be adjusted in a way the system doesn't support, etc.

Describe the solution you'd like
Add a popup dialogue when shift-clicking one of the damage application buttons (including healing and focus) that lets you input a positive/negative integer which will be added to the final applied value. (So after deflect and other modifiers occur.)

Describe alternatives you've considered
People can just manually increase/decrease the amount of health lost/gained after the fact, but this option would work with the chat cards nicely.

Version
0.3.0

Additional context
N/A

Checklist:

• I have searched the existing issues to ensure this feature has not already been requested.