fix(platform): apply room action battle flags

cocoscreator_projects/YouleNexus/assets/framework/platform/stores/platform-store.ts

@@ -369,6 +369,16 @@ function parseSeatAction(value: ParsedSeatPayload): {
   return { seat, raw };
 }
 
+function stageAfterOptionalDeskwar(
+  raw: Readonly<Record<string, unknown>>,
+  currentStage: number,
+): number {
+  if (!hasOwn(raw, 'deskwar')) return currentStage;
+  return requireProtocolFlag(raw.deskwar, '$.event.raw.deskwar') === 1
+    ? 1
+    : currentStage;
+}
+
 function requireOccupiedSeat(room: InsideRoomState, seat: number): number {
   if (seat < 0 || seat >= room.seatPlayerIds.length) {
     throw new RangeError('$.event.seat: expected room seat range');
@@ -572,6 +582,7 @@ export class PlatformStore {
     if (room.seatPlayerIds.includes(joined.player.playerid)) {
       throw new RangeError('$.event.raw.playerid: duplicate player seat');
     }
+    const stage = stageAfterOptionalDeskwar(event.raw, room.stage);
 
     const player = Object.freeze(joined.player);
     const entities = Object.freeze({
@@ -598,6 +609,7 @@ export class PlatformStore {
         seatPlayerIds: Object.freeze(seatPlayerIds),
         readySeats: Object.freeze(readySeats),
         offlineSeats: Object.freeze(offlineSeats),
+        stage,
       }),
     }));
   }
@@ -614,6 +626,7 @@ export class PlatformStore {
     if (player === undefined) {
       throw new RangeError('players.entities: occupied seat has no canonical player');
     }
+    const stage = stageAfterOptionalDeskwar(event.raw, room.stage);
     const entities = Object.freeze({
       ...previous.players.entities,
       [playerid]: Object.freeze({ ...player, isprepare: 1 }),
@@ -625,7 +638,7 @@ export class PlatformStore {
         selfPlayerId: previous.players.selfPlayerId,
         entities,
       }),
-      room: Object.freeze({ ...room, readySeats }),
+      room: Object.freeze({ ...room, readySeats, stage }),
     }));
   }