Burn momentum

Burns momentum, resetting your Active Character's momentum to their momentum reset value, and replacing the action value of the last action roll with your previous momentum value, then it records this operation in your current journal with a `burn` mechanics node. If done after Make a move, this will automatically change the result of the roll.

This command can only be used when you've activated the Use character system Setting, and thus requires an actual Active Character to work at all.

If you don't want to use the Character System but still want to record burning momentum, you can write the `burn` mechanics node directly into your journal, and it will also alter the displayed Move result.

Example

Face Danger

Action die: 4
Stat: 2
Adds: 0
Score: 6
Challenge die 1: 8
Challenge die 2: 9
Outcome: Miss

From: 9
To: 2
New score: 9
Challenge die 1: 8
Challenge die 2: 9
Outcome: Weak hit

```iron-vault-mechanics
move "Face Danger" {
    roll action=4 stat=2 adds=0 vs1=8 vs2=9
    - "ouch"
    burn from=9 to=2
	- "that's better..."
}
```