feedback1 WD: a form change clip plays out; browser check of the forms

- render/spine.js: no attack (wind-up or 'atk') cuts a form's change clip short;
  a knocked-out 逐火 no longer reports its last attack in the snapshot.
- test/render/feedback1-forms.browser.test.js (opt-in RENDER_E2E=1): the real
  sim in headless Chrome on 战场#01 — 转译基底·α A_* → A_Die_B → B_* → B_Die,
  a 深池逐火战士 knocked out in front of its blocker: Die → the 隐匿 ember on
  Idle_2, beaten → Die_2.
- PLAYING.md: the 余烬 and 转译基底 rules for players.

server/sim/content/enemies.js

@@ -833,6 +833,7 @@ function husk({ hits, delay, stealthy = true, unblock = false, onHusk = null, ke
       a.noAtk = e.profile.noAttack;
       a.max = a.max ?? e.base.maxHp;
       e.profile.noAttack = true;
+      e.lastAttackAt = -Infinity;                         // the snapshot shows no attack of the fallen warrior
       setHits(e, hits);
       hitCount(b, e, true);
       b.addBuff(e, { key, visible: true, persist: true, flags: { disarm: true, ...(stealthy ? { stealth: true } : {}), ...(unblock ? { unblockable: true } : {}) } });