refactor: extract inline HTML to templates, split oversized files, fix bugs

- Extract all inline HTML from JS into 21 Handlebars templates (chat/, dialogs/, ui/)
- Split utils.mjs (1507) into barrel + helpers.mjs, combat.mjs, d30.mjs
- Split roll.mjs (1632) into barrel + roll-base.mjs, roll-prompt.mjs, roll-combat.mjs, roll-damage.mjs
- Split lethal-fantasy.mjs (1426) into bootstrap + chat-reaction.mjs
- Fix: missing async on injectDiceTray (free-roll.mjs:29 SyntaxError)
- Fix: weapon._id fallback for deserialized chat-message weapon objects
- Fix: missing await on rollModifier.evaluate() calls in roll-combat.mjs
- Fix: choices→choicesList ReferenceError in utils.mjs
- Fix: add 12 missing i18n keys (chooseWeapon, chooseSave, attackRoll, etc.)
- Fix: restore sideLabel in bonus-die-select.hbs
- Clean: remove dead messageContent param, console.log→log()
- Style: barrel files preserve existing import paths

module/documents/roll-damage.mjs

@@ -0,0 +1,39 @@
+/**
+ * Evaluate a spell/miracle damage formula with per-die explosion, then post to chat.
+ * Explosion dice are shown manually via showForRoll; the main roll is shown automatically
+ * by toMessage() (which triggers Dice So Nice via its createChatMessage hook).
+ * Append "NE" to the formula to disable explosion.
+ *
+ * @param {string} formula    Dice formula, e.g. "1d8", "2d6", "1d8NE"
+ * @param {Object} rollOpts   Options for LethalFantasyRoll (rollType, actorId, defenderId, etc.)
+ * @returns {Promise<ChatMessage>}
+ */
+export async function rollSpellDamageToMessage(formula, rollOpts) {
+  const roll = new this(formula, {}, rollOpts)
+  await roll.evaluate()
+  const shouldExplode = !/NE$/i.test(formula)
+  const diceResults = []
+  let diceSum = 0
+  for (const term of roll.dice) {
+    const singleDice = `1D${term.faces}`
+    const termResults = Array.from(term.results)
+    for (const r of termResults) {
+      let diceResult = r.result
+      diceResults.push({ dice: singleDice.toUpperCase(), value: diceResult })
+      diceSum += diceResult
+      if (shouldExplode && term.faces > 0) {
+        while (diceResult === term.faces) {
+          const xr = await new Roll(singleDice).evaluate()
+          // Optional chaining guards against unexpected roll structure
+          diceResult = xr.dice?.[0]?.results?.[0]?.result ?? (term.faces - 1)
+          diceResults.push({ dice: `${singleDice.toUpperCase()}-1`, value: diceResult - 1 })
+          diceSum += (diceResult - 1)
+          term.results.push({ result: diceResult, active: true })
+        }
+      }
+    }
+  }
+  roll.options.diceResults = diceResults
+  roll.options.rollTotal = diceSum
+  return roll.toMessage()
+}