Playtest #4 fixes: tile picking, knocked-down state, element gauges, draft timer, live stats, shop items, drones, 赫默, 炎佑, UI flash

- #1 picking by the tile under the pointer (prep, battle, pen, equipment drops); the dragged model stays
  under the pointer (mouse and touch); pixel probe removed; phone ghost-click on the underframe fixed
- #2 two-tap confirm on 机变 cards (like the shop)
- #3 a 同盟 room with one human is untimed like 独立模拟 (no countdown outside battles)
- #4 strategy draft: one synced countdown, 30 s per human turn, timeout takes the highlighted band
- #5 special 维式重锤 (4) and 突变细胞 no longer sold; item card shows where they come from
- #6 operator skill-mode sounds no longer play on normal attacks (纯烬艾雅法拉 and 55 others)
- #7 detail card shows live battle stats and the prep-time battle-start stats (g.unitStats)
- #8 official element gauges on units; burst cooldown (阻回) per PRTS
- #9 knocked-down operators stay on their tile with a redeploy countdown ring
- #10 drone behaviour per PRTS (暴鸰, 先兆者 shells, 黑云, 萨科塔之眼)
- #11 赫默's drone only from her skill; placeable summons limited to talent tokens
- #12 炎佑 stays where it is with no enemies; 祛恶之焰 as a continuous channel
- #13 the occasional giant bond icon (loading texture scaled ×46) fixed
- docs (DESIGN §18), recordings, data and tests updated (2467 unit tests, all browser suites green)

server/sim/ai.js

@@ -618,8 +618,13 @@ function enemyAttack(b, e) {
   const attackId = ++b._attackSeq;
   const type = def.dmgType === 'heal' ? 'arts' : def.dmgType;
   const rangedShot = radius > 0 && !(e.blockedBy && targets[0] === e.blockedBy && radius < 1);
+  // content-resolved attacks (`e.profile.deferHit`: 帝国炮火先兆者's shell landing 3 s later): the attack itself happens
+  // — the 'atk' event (kind `e.profile.shot`, drawn by the content's own fx), cooldown, pause, the 'attack' hook — and
+  // the content's 'attack' handler deals its damage
+  const deferred = !!(e.profile && e.profile.deferHit);
   for (const t of targets) {
-    b._ev(['atk', e.id, t.id, rangedShot ? 'enemy' : 'none']);
+    b._ev(['atk', e.id, t.id, deferred ? (e.profile.shot || 'none') : rangedShot ? 'enemy' : 'none']);
+    if (deferred) continue;
     const hit = (tt) => {
       if (!tt || !tt.alive || !e.alive && !rangedShot) return;
       b.dealDamage(e, tt, { amount: e.s.atk * (e.profile?.atkScale ?? 1), type, isAttack: true, attackId });