Automatically apply the correct HP after rolling hit dice

[anthonyronda]

New Feature or Changed Behaviour

Current behavior:
By clicking the HD label of the Hit Die box, a roll will post to chat with the current number of hit dice, modified by the CON modifier multiplied by the current level of the PC. The user has to type the new HP max into the character's sheet, given the rules of the game laid out in the SRD

new behavior:
By clicking the HD label of the Hit Die box, a window will appear showing all three elements of determining the new HD of a player character:

• Their current hit dice
• Their current level
• Their CON modifier number

These may be editable, since they may have clicked this before changing the hit dice or level on their sheet. Upon submitting, the result of the roll will post to chat, and the new max HP (optionally: the new HD and level) will be updated on their character sheet automatically. This includes making sure the HP always increases by at least 1.

Why?

The current level up flow requires numerous clicks and typing into fields from the user, the HD flow is a large and easy to automate part of this process.

By showing the user that we're using the level and the HD to help calculate the new HP, we're communicating how CON modifier stacks with level (a commonly mistaken rule)

This was part of a request/conversation stemming from bug #195

Code of Conduct

• I agree to follow this project's Code of Conduct

[anthonyronda]

Additionally, the new flow should account for the possibility of multiple classes
We will refer to the advanced fantasy rulebook's rules for Multiple Classes > Hit Points (this will have to have a provision for saving fractions of a hit point without applying them to HP)