fix: cache results.length before explosion loop to prevent double-count

Pushing explosion dice to DieTerm.results made the for loop
condition (j < results.length) grow mid-iteration, re-processing
the explosion result as a normal die. This produced spurious
entries like `1D6 → 4` alongside the correct `1D6-1 → 3`.

Fixes prompt() (for loop) and rollSpellDamageToMessage()
(for...of) by caching result count / snapshotting the array
before iterating.

module/documents/roll.mjs

@@ -616,8 +616,10 @@ export default class LethalFantasyRoll extends Roll {
 
     let singleDice = `1D${maxValue}`
     for (let i = 0; i < rollBase.dice.length; i++) {
-      for (let j = 0; j < rollBase.dice[i].results.length; j++) {
-        let diceResult = rollBase.dice[i].results[j].result
+      const dieResults = rollBase.dice[i].results
+      const resultCount = dieResults.length
+      for (let j = 0; j < resultCount; j++) {
+        let diceResult = dieResults[j].result
         diceResults.push({ dice: `${singleDice.toUpperCase()}`, value: diceResult })
         diceSum += diceResult
         if (hasMaxValue) {
@@ -627,7 +629,7 @@ export default class LethalFantasyRoll extends Roll {
             diceResults.push({ dice: `${singleDice.toUpperCase()}-1`, value: diceResult - 1 })
             diceSum += (diceResult - 1)
             // Add to DieTerm results so DSN/Foundry display shows explosion dice
-            rollBase.dice[i].results.push({ result: diceResult, active: true })
+            dieResults.push({ result: diceResult, active: true })
           }
         }
       }
@@ -1592,7 +1594,8 @@ export default class LethalFantasyRoll extends Roll {
     let diceSum = 0
     for (const term of roll.dice) {
       const singleDice = `1D${term.faces}`
-      for (const r of term.results) {
+      const termResults = Array.from(term.results)
+      for (const r of termResults) {
         let diceResult = r.result
         diceResults.push({ dice: singleDice.toUpperCase(), value: diceResult })
         diceSum += diceResult