feedback5 WE1: 庇护 is one effect per unit — 宴, 余, 缪尔赛思, 赫拉格, 左乐 and 赫德雷 join the shared key (follow-up 18)

gamedata_const ba.protect / PRTS 术语 庇护 "受到的物理和法术伤害降低相应比例（同名效果取最高）": the strongest source holds; the
自选 kits already used battle.applyStrongest('protect'), these six multiplied private cuts with it.

- kits/shared/tier1.js: PROTECT, protectMods, PROTECT_TICK_HOLD and holdProtect (applyStrongest on the shared key).
- 宴 / 赫拉格 / 左乐 (below their HP threshold): refreshed every tick and at each hit on them; 余 (blocking) and 缪尔赛思's
  melee copies at their old cadence; 赫德雷's 庇护 joins the key, his CRU-X 物理伤害 + becomes its own instance. 左乐 keeps the
  PRTS S2 ordering (his own 庇护 newer than his barrier cuts behind it); 行险 drops his own held 庇护 for its 0.1 s
  re-judgement [ASSUMED: another source's returns with its next refresh]. 遥's bubbles stay separate (the client's
  damage_resistance[bonus] multiplies with the common damage_resistance[inf]).

Golden: no scenario moved — no unit of the corpus holds two 庇护 at once, and one source alone cuts exactly as before.

Tests: test/content/feedback5-protect.test.js (new, 2); kits_t6 (余), kits_alt_t6 (缪尔赛思), op_hodrer updated to the
shared key; kits_t1t2, op_helage, op_zuole pass. Docs: SIM.md §3, kits/README.md checklist 9.

server/sim/content/kits/README.md

@@ -319,7 +319,8 @@ Each item is a mistake this project already made once. Tick every one for every
   `test/match/feedback1-placement.test.js` "#9 data: 狼群 and 流形 are owner-range summons" (DESIGN §20.1, §21.3);
   `test/content/playtest6_summons.test.js`, `tokens_summons.test.js`; `feedback1b_kits.test.js` "B3 维娜·维多利亚 S3".
 - [ ] **9. Status effects** — every status applied, with its official duration and stacking (寒冷 on 寒冷 ⇒ 冻结 for the
-  longer cold, 沉默 removes abilities, 恐惧, 睡眠, 浮空 …; "同名效果取最高" = `applyStrongest`). Examples:
+  longer cold, 沉默 removes abilities, 恐惧, 睡眠, 浮空 …; "同名效果取最高" = `applyStrongest`; 庇护 = the shared
+  `PROTECT` key, `holdProtect` in `shared/tier1.js`). Examples:
   `test/sim/combat.test.js` "cold on cold ⇒ freeze for the longer cold …", "sleep: target is untargetable and
   inactive; fear stops enemy attacks", "statuses: sleep = invulnerable except `hitSleep` attackers; levitate …";
   `enemies_bosses.test.js` "沉默: exactly the abilities whose handbook line is SILENCE-flagged can be silenced".