Support group battle preparation powers

game/battle-power-question.ts

@@ -1,4 +1,5 @@
 import { voiceChoices } from './battle-cards';
+import { coalitionBattleBeneficiary, type CoalitionBattlePreparationContext } from './coalition-battle-preparation';
 
 export type NativeBattlePower = 'voice' | 'prescience';
 export type BattlePowerClaim =
@@ -15,7 +16,7 @@ export type NativeBattlePowerOpportunity = {
   event: string; territory: string; power: NativeBattlePower; owner: string;
   beneficiary: string; target: string; ready: boolean;
 };
-export type NativeBattlePowerGame = {
+export type NativeBattlePowerGame = Omit<CoalitionBattlePreparationContext, 'players' | 'status'> & {
   status: string;
   phase: number;
   players: readonly { id: string; faction: string; ally?: string | null }[];
@@ -110,9 +111,8 @@ export function nativeBattlePowerOpportunity(game: NativeBattlePowerGame, actor:
   const side = (kind: NativeBattlePower) => {
     const owners = game.players.filter(player => player.faction === (kind === 'voice' ? 'beneGesserit' : 'atreides'));
     if (owners.length !== 1) return null;
-    const owner = owners[0], combatants = [battle.attacker, battle.defender];
-    const beneficiary = combatants.includes(owner.id) ? owner.id : owner.ally && combatants.includes(owner.ally) &&
-      game.players.some(player => player.id === owner.ally && player.ally === owner.id) ? owner.ally : null;
+    const owner = owners[0];
+    const beneficiary = coalitionBattleBeneficiary(game, owner.id, battle.attacker, battle.defender, true);
     return beneficiary ? { owner: owner.id, beneficiary,
       target: battle.attacker === beneficiary ? battle.defender : battle.attacker } : null;
   };