Add critical hits when rolling damage

[averycrespi]

Changes:

• When a DAMAGE button is Control-clicked, the roll should be treated as a critical hit
• The toast message should be changed to: "$character rolled critical $weapon damage!"
• The emote should be changed to: "/em : $character rolls critical $weapon damage"
• All damage dice (not modifiers) should be doubled. Example: 1d4 + 2 becomes 2d4 + 2
• A tooltip should be added to the buttons, which says: ctrl+click for critical hit

Notes;

• Extract the dice using the following regex: [0-9]+d[0-9]+, split on the d, double, then recombine
• We need to wait for Support compact roll buttons #88 to avoid redoing work