feedback6: merge R21B — 联防 plays on the round's battlefield again, its terrain, crates, water, devices and runes as in 0.1.4 (the owner's report 「联防阶段地形全消失了」 and knowledge of the official mode, GitHub #244's tournament video; 0.2.0's escaped level was the placeholder road every wave-template level carries); the 联防 battle input is byte-identical to 0.1.4's in 20 cases; 乌尔比安's comment keeps both streams' sentences; golden as R21B's commit (unite-1 / unite-2 back to their stages, coop2-NORMAL-3, coop2-HARD-4, coop3-ABYSS-5, coop4-ABYSS-7, coop2-NORMAL-8-serverrun, coop2-NORMAL-14-standins), the merged tree differs from the branch only in R21A's boss pair fields

server/sim/battle/economy.js

@@ -57,7 +57,8 @@ export class BattleEconomy {
    * whose half of the field it fell on: PRTS 卫戍协议：盟约 决策 "该敌人于对应玩家所属区域倒下时，使相应玩家获得额外资金"
    * [ASSUMED for 联防: no source names the payee of a death nobody caused there]. Until 0.2.0 that fallback was the
    * leaker, who has no entry in a 联防 battle, and addCoins dropped the coins (community report of 2026-10-06
-   * 「被源石地板烫死的悬赏没给赏金」: until 0.1.3 the 联防 field was the round's map, 战场#04's 活性源石 included).
+   * 「被源石地板烫死的悬赏没给赏金」: in 0.1.x the 联防 field was the round's map, as it is again since 0.2.1, 战场#04's
+   * 活性源石 included).
    */
   _bountyPayee(unit, killer = null) {
     if (killer && killer.side === 'ally' && killer.ownerId != null && this._pp(killer.ownerId)) return killer.ownerId;