feedback5: merge CB4 — community reports (enemies / bosses): a 突袭 member lands only on its own player's board (never a boss field's hand / 临时整备区 rows nor the other half of a 联防 or boss field), a silenced 萨卡兹枯朽战士 leaves no 污染秽蚀, 萨卡兹穿刺手's acceleration ends with a stun or 束缚 and its first hit after a block adds move speed × 600 as its own instance, 自制投石机 ignores its block when it picks a target (no attack on the 排气格栅's hidden blocker), the briefing types' 7–9 waves, 新硎's 断刃, a freed prisoner in 联防, 鸭爵's 0–2 swaps and the moving leaders' routes pinned, four reports not reproduced; §25.18; golden: vs feedback5 CB4's own rules — roster-016, boss-boss_2/3/4/5/6-pair, hidden-boss_8/10-pair, standin-04/06/08, diy-028, diy-124, matches solo-NORMAL-1, solo-HARD-1, solo-ABYSS-1, coop2-HARD-4, coop4-ABYSS-7, coop2-NORMAL-8-serverrun; vs CB4 exactly what feedback5 changed since its base (CB2's roster 13 / bonds 7 / fields 6, CB5's 18 bot matches)

Merge fix: test/sim/facing-invariance.test.js — the 突袭 rotation check put its enemy on the board's top row (9, 9),
so the facing-RIGHT landing tile it expected, (8, 8), lies above the player's board, where CB4's onOwnBoard rule (the
official 再部署 goes where the player deploys; community reports 40 / 16.3) now refuses it; the member landed on
(10, 8). The enemy stands at (10, 6), inside rows 9–12 / cols 2–10, so all four diagonal tiles are candidates in every
direction and the test checks the facing tie-break as before. It failed on fb5-cb4 itself (the stream did not run the
file). The §25 intro's stream lines joined into one sentence again.

Golden moves outside CB4's commit list are its rules on feedback5's paths (instrumented): solo-HARD-1 and solo-ABYSS-1
now have silenced 枯朽战士 deaths (8 / 15) and 突袭 candidates the own-board filter refuses; coop2-ABYSS-10-boosted,
coop2-NORMAL-3 and coop2-NORMAL-14-standins (in CB4's list) have no silenced 枯朽战士 death on this path, and their
digests are identical with the own-board filter switched off (the refused tiles were never the chosen ones).

Gate: non-browser suites 4968 / 4968, npm run golden ok, test/golden.test.js 9 / 9, lint 0 errors, check:imports ok,
typecheck ok, docs-consistency + docs-paths 31 / 31.

docs/design/engine.md

@@ -122,7 +122,7 @@ Engine helpers (content must use these, never touch internals): `battle.dealDama
 - **Blocking** (contact radius, PRTS 游戏数据基础 §阻挡半径 / 作战机制 "中点判定…案例：阻挡"; `constants.js BLOCK_RADIUS`, `Battle._checkBlock`, §19.2): an operator with free capacity blocks an unblocked, blockable enemy whose position lies within its block radius of its centre — ground 0.7071 (squared 0.49999037), 0.8944 × the blocker's 阻挡半径倍率 for blockFly units vs flyers (起飞; mod `blockRadiusScale` = 倍率 − 1 — PRTS 游戏数据基础 "飞行阻挡半径 = 0.8944 × 阻挡半径倍率", 凯尔希·思衡托 +0.23), devices 0.4472 (阻隔工事 / 障碍物); air units (FLY, 近地悬浮, 浮空) only by blockFly units. A ground enemy is never blocked by a unit standing on a tile ground units cannot pass (围墙 / 围栏: PRTS 地形机制 "部署在其中的单位，若当前阻挡类型为'地面阻挡'则无法阻挡敌人" — an enemy pushed or pulled against the fence walks on; air blocking there stays [ASSUMED], §21.23) nor by an airborne (起飞) unit, which blocks flyers only (§21.22). An enemy holding 不可阻挡 (PRTS 异常效果 BLOCK_FREE 「无法阻挡/被阻挡，自动解除阻挡」) — `unblockable` (恐惧, 诱导, enemy abilities), 浮空, and 沉睡 (SLEEPING = 无法行动+无敌+不可阻挡) — is never blocked and is released at once: a sleeping enemy frees its blocker's slot, stays where it is and, once awake, is blocked again only by a blocker with room (§24.9). The nearest such operator wins (ties: scan order [ASSUMED]). It is re-checked every tick, moving or not, so another operator in contact with room takes the enemy over when its blocker dies, is withdrawn or is stunned, and an operator whose capacity frees up grabs an overlapping enemy; one that finds no room walks on. A head-on enemy stops at contact (≈ 0.71 tile), outside the blocker's tile. Enemy uses `blockCnt` capacity (default 1). Blocked enemies stop moving and attack their blocker if melee (or anyone in range if ranged, blocker first). **Every blocker** — melee units (重装要塞 / 领主 / 哨戒铁卫 included), summons and a ranged operator on a melee tile alike — whose attack hits enemies may always target the enemies it blocks, in range or not, whatever its facing, and targets them first ("可以选择且优先选择阻挡单位", PRTS 选择器; the user's rule after playtest #6, "阻挡了就一定要能打到": officially the collision pushes a blocked enemy to its blocker's front; `Battle.blockedTargets`, `targeting.js sortEnemyTargets`; §20.3 — it replaces the playtest #5 QA's melee-only restriction of §19.2). A healer (dmgType `heal`, or a skill attack turned into a heal) selects injured allies only and keeps healing while it blocks (PRTS 卫戍协议/帮助 "对于医疗干员（咒愈师分支除外），攻击目标为需要治疗的单位"; §21.17); 咒愈师 follow the blocker rule. The huge leaders are 自缚 + unblockable (§7).
 - **Operator attacks**: every `interval` s if a valid target exists; targets = up to `maxTargets` (default 1) from `unitsInGrid(rangeGrid)` (a `rangeAoe` profile — 阵法术师, 轰击术师 — takes every selectable enemy in range, §21.18; 「同时攻击阻挡的所有敌人」 — 强攻手 / 重剑手 / 推击手 and the skills worded so, `hitAllBlocked` — up to the block count, never fewer than 1, since 0.2.0: PRTS 分支特性信息 "普通攻击最大目标数等于阻挡数（不会低于1）"), priority: (1) the enemies it blocks (every blocker, in range or not, §20.3), (2) profession/trait priorities (e.g. fly-first snipers, `trait` text parsed by build-data into `targetPriority`), (3) enemy with the **least remaining path distance** to its goal, ties → earliest spawned. Melee (no ranged trait) and ground-only attacks cannot hit air units (`Unit.isFlying`: FLY, or a 近地悬浮 / 浮空 enemy — PRTS "算作空中单位", §19.1). Stealthed enemies can't be targeted unless blocked or revealed — or within 3 s of a block's end (§22.8). Ranged ops fire projectiles (speed ~12 tiles/s, instant for melee/arts-beam classes as data indicates); damage applies on impact; a 锁定攻击范围 AoE (`rangeAoe`) strikes every selectable enemy on its range at once with instant hits (§21.18).
 - **Healers** (`dmgType heal`): target the ally in range with the lowest HP% below 100%, never a 禁疗 / 孤立 unit (tokens.json `abnormal`, `noHeal`; §20.3; 史尔特尔 during 余烬, §22.7), and never the enemies they block — also while blocking (§21.17); do nothing otherwise (SP still regenerates).
-- **Enemy AI**: follow the route (checkpoints; WALK paths recomputed on the grid when devices change); when blocked stop & fight (`dmgType 'none'` enemies never attack unless content arms them through `e.profile` — 转译基底's armed forms, §21.4); ranged enemies (`rangeRadius > 0`) attack ops whose 0.25 collider touches their radius (centre distance ≤ `rangeRadius` + 0.25, §3, §20.4): the enemy's own target rule filters the candidates first (`profile.canTarget`: 只攻击地面单位 …), then priority blocker → special priority → highest taunt → **latest deployed** (`aggroSeq`) — PRTS 索敌 "阻挡→特殊优先级→仇恨值→最早出现"; a stealthed ally is attacked only by the enemy it blocks (§19.1), and an enemy's area effects — splash, blasts, area skills, zones, jumps — and buff auras skip it unless it blocks that enemy, while 迷彩 does not protect from splash and the other area effects (`targeting.js areaSelectable` / `auraSelectable`, §22.12); an airborne (起飞) ally is never a ground enemy's selection — picks, area damage, zones and statuses skip it, while 无视无法选择 abilities, direct picks, debuff ticks and flying units still reach it (§21.22); unblocked, they stand for each attack's clip (enemies.json `attackAnim`: its wind-up before the strike and the rest of the clip after it, shortened when the attacks come quicker than the clip; `ATTACK_PAUSE = 0.35 s` after the strike when no clip is known; a 「不停止移动」 attacker never stops; §22.14). Every enemy attack strikes at its clip's damage frame after its swing starts — the first one of a contact too —, and a stun / freeze / sleep / 浮空, hiding, 缴械, 恐惧 or 战栗 (blocked) before that frame cuts the swing: no strike, the next swing starts from its wind-up (0.2.0, `ai.js attackWindup`; PRTS 状态机 / 异常效果 STUNNED; no clip known: no wind-up). FLY enemies ignore ground obstacles (only blockFly units block them) and follow their checkpoint route. A feared enemy runs between random 恐惧可达地块 away from the source (PRTS 诱发移动; `fear.js`); 恐惧 outranks 诱导; the 恐惧 / 诱导 walks re-plan from where the enemy stands after a push or an obstacle change, and the route re-plans when they end (§20.4).
+- **Enemy AI**: follow the route (checkpoints; WALK paths recomputed on the grid when devices change); when blocked stop & fight (`dmgType 'none'` enemies never attack unless content arms them through `e.profile` — 转译基底's armed forms, §21.4); ranged enemies (`rangeRadius > 0`) attack ops whose 0.25 collider touches their radius (centre distance ≤ `rangeRadius` + 0.25, §3, §20.4): the enemy's own target rule filters the candidates first (`profile.canTarget`: 只攻击地面单位 …), then priority blocker → special priority → highest taunt → **latest deployed** (`aggroSeq`) — PRTS 索敌 "阻挡→特殊优先级→仇恨值→最早出现"; a stealthed ally is attacked only by the enemy it blocks (§19.1) — and not even by that one when its 索敌不受阻挡影响 (自制投石机, `profile.blockFree`: it selects as if unblocked, §25.18) —, and an enemy's area effects — splash, blasts, area skills, zones, jumps — and buff auras skip it unless it blocks that enemy, while 迷彩 does not protect from splash and the other area effects (`targeting.js areaSelectable` / `auraSelectable`, §22.12); an airborne (起飞) ally is never a ground enemy's selection — picks, area damage, zones and statuses skip it, while 无视无法选择 abilities, direct picks, debuff ticks and flying units still reach it (§21.22); unblocked, they stand for each attack's clip (enemies.json `attackAnim`: its wind-up before the strike and the rest of the clip after it, shortened when the attacks come quicker than the clip; `ATTACK_PAUSE = 0.35 s` after the strike when no clip is known; a 「不停止移动」 attacker never stops; §22.14). Every enemy attack strikes at its clip's damage frame after its swing starts — the first one of a contact too —, and a stun / freeze / sleep / 浮空, hiding, 缴械, 恐惧 or 战栗 (blocked) before that frame cuts the swing: no strike, the next swing starts from its wind-up (0.2.0, `ai.js attackWindup`; PRTS 状态机 / 异常效果 STUNNED; no clip known: no wind-up). FLY enemies ignore ground obstacles (only blockFly units block them) and follow their checkpoint route. A feared enemy runs between random 恐惧可达地块 away from the source (PRTS 诱发移动; `fear.js`); 恐惧 outranks 诱导; the 恐惧 / 诱导 walks re-plan from where the enemy stands after a push or an obstacle change, and the route re-plans when they end (§20.4).
 - **Damage**: phys `max(A − max(0, D×(1−defIgnorePct) − defIgnoreFlat), 0.05·A)`; arts `max(A × (1 − R'/100), 0.05·A)` with `R' = max(0, R×(1−resIgnorePct) − resIgnoreFlat)`; true = A; 元素伤害 ('elemental') `max(A × (1 − 元素抗性/100), 0.05·A)`. Then × `dmgDealtMul` (source) × `dmgTakenMul` & type-specific taken multipliers (target) × `dmg.mul` — 元素伤害 takes 元素脆弱 (`elementalTakenMul`) alone, not `dmgTakenMul` (脆弱 = "受到的物理、法术、真实伤害提升"). Then **限伤**: on a leader (`isBoss` — the 10 bossInfoDict enemyIds and their mirrored copies; never parts, drones or escorts) in a `'boss'` / `'hidden'` battle a hit with `ceil(final) ≥ 300000` is cancelled — no HP or pool loss, no credit, no damage number, no `damaged` / kill (`shared/constants.js BOSS_HIT_LIMIT`, `damage.js leaderHitCancelled`, after every multiplier and the hit-step blocks, before HP shields; `loseHp` too — a part's 传递, but not 胄's drone link, a share of the pool that is no hit (`noHitLimit`, §25.13.4); the client's `MAX_BATTLE_DAMAGE`, §20.12). Then shields absorb; dodge checks for phys/arts. Element damage fills a gauge (1000; enemy leaders 2000) × `elemTakenMul` × max(0.05, 1 − 损伤抵抗/100), 损伤抵抗 = data `epResistance` (PRTS 元素; the 5 % floor of DMG_e, PRTS 游戏数据基础). An element fill on a target with no HP left is refused (damage.js `hasHp`: no burst on a corpse). A full gauge bursts with the side-specific official effects, as **无来源** damage (no damage-dealt multiplier or penetration of the unit that filled the gauge, which keeps the kill and the stats; §19.5) (sim/constants.js `ELEMENT`; operators: 灼燃 1200 arts + RES −20, 神经 stun 10 s then 1000 true, 凋亡 15 s of 阻回 (`noSp`: no SP gain of any kind) + 静默 with −1 SP/s and 100 arts/s, 侵蚀 DEF −100 then 800 phys; enemies: the "·我方" terms). Every burst starts a **爆发冷却** = its duration (灼燃 / 神经 / 侵蚀 10 s — enemies' 侵蚀 8 s — 凋亡 15 s) during which NO element of the unit fills or can be recovered; when it ends every gauge of the unit resets (§18.3).
 - **Leak**: an enemy reaching its goal is removed, counted as leaked for its field owner (`sourcePlayerId` for unite). LP accounting is done by the match, not the battle.
 - **Results**: `damageDealt` / a unit's `dmg` count only HP removed from the other side — a unit's own drain or 流失 and friendly damage are the target's `taken` only (§21.12).