0.2.4-dev: round-29 community fixes and the official shared card pool

- Shared card pool and item stock as in the official mode (the owner's request, from the 路标档案馆 video and public notes): solo low-tier exceptions, co-op operators x2, shared item stock with special-item exceptions, normal / advanced occupancy 1 / 2, re-check on buy, 机变 exhaustion, release on consume / destroy / elimination; 整备 never exceeds stock; invariant held <= cap.
- 突袭: one taunt-first reselect right after a revive (the owner's rule); ordinary polls and redeploys keep the 0.2.3 rule; a revive on an enemy's tile stays. #475: online boss / hidden-boss Raid may land on the empty half (owner-limited scope).
- 浊心斯卡蒂 S1 x 坚守 no longer bounce redirected damage, and the two shares conserve the hit (idea of PR #464 by @HappyTanuki).
- Operator fixes adapted from PRs by @Xinglan233 (#459 哈洛德 S2 elemental trigger, #460 涤火杰西卡 shield on the four adjacent tiles, #461 家族徽章 first hit after stealth, #462 松果 S2 regrow per deploy); 克莱门莎 S2 splash 1.1 / 100% ATK and air auto-trigger (#467); 白面 copying 歌蕾蒂娅 / 余 skips the three-member condition (#473, the owner's video).
- 香槟炸弹 is not chosen by friendly auras / heals (PR #468 / #476 by @Siornya); 琳琅诗怀雅 coin balance (PR #450 by @IceCodeNew); Touch prep display (PR #451 by @YinqiMargatroid); lobby header (PR #471 by @YuriRestia); Japanese UI terms (PR #448 by @scutkane).
- AI-only boss countdown grace, render-failure cache / recovery without restarting a battle, device units kept on a same-field re-entry, DIY detail / skill previews, large-text result buttons.
- golden: battle families equal 0.2.3 except diy-135 / diy-136 (克莱门莎); all 18 release matches move through the shared pool, every flip named in docs/history/0.2.4.md §29.12; two coverage scenarios added.

server/match/invariants.js

@@ -3,7 +3,8 @@
 // (test/match/harness.js checkInvariants asserts the list is empty) and by tools/matchrun.mjs --check sweeps.
 //
 // collectViolations(m) → string[] (empty when every invariant holds):
-//   pool     0 ≤ left ≤ cap and left + Σ copies held by pieces == cap per base chess; non-pool chess hold 0 copies;
+//   pool     raw balance ≤ cap and raw balance + Σ copies held by pieces == cap (public availability is clamped at zero) per base chess; non-pool chess hold 0 copies;
+//            every capped shop item is held by at most its cap (normal occupies 1, upgraded 2; effect-only items have no cap)
 //            a player's 自选 stock (0.2.0, player/diy.js) the same against its own pieces of each slotted slot — a DIY
 //            piece is always a slotted slot of its owner's, and a DIY shop / reward card one of its stocked slots
 //   economy  funds / pendingFunds non-negative integers, LP finite, shop level in range, prices ≥ 0
@@ -186,7 +187,7 @@ export function collectViolations(m, { limit = 25 } = {}) {
     }
     // 自选 stock accounting (player/diy.js): left + held == cap per slotted slot; a slot without stock holds nothing
     for (const [base, e] of ps.diyStock ? ps.diyStock.entries : []) {
-      if (!(e.left >= 0 && e.left <= e.cap)) fail(`${id}: 自选 stock ${base}: left ${e.left} cap ${e.cap}`);
+      if (!(Number.isInteger(e.left) && e.left <= e.cap)) fail(`${id}: 自选 stock ${base}: balance ${e.left} cap ${e.cap}`);
       const h = diyHeld.get(base) || 0;
       if (e.left + h !== e.cap) fail(`${id}: 自选 stock ${base}: left ${e.left} + held ${h} != cap ${e.cap}`);
     }
@@ -195,12 +196,23 @@ export function collectViolations(m, { limit = 25 } = {}) {
 
   // shared pool accounting
   for (const [base, e] of m.pool.entries) {
-    if (!(e.left >= 0 && e.left <= e.cap)) fail(`pool ${base}: left ${e.left} cap ${e.cap}`);
+    if (!(Number.isInteger(e.left) && e.left <= e.cap)) fail(`pool ${base}: balance ${e.left} cap ${e.cap}`);
     const h = held.get(base) || 0;
     if (e.left + h !== e.cap) fail(`pool ${base}: left ${e.left} + held ${h} != cap ${e.cap}`);
   }
   for (const [base, n] of held) if (!m.pool.has(base) && n !== 0) fail(`non-pool chess ${base} holds ${n} copies`);
 
+  // Shared shop equipment. The chess pool above may go negative (Mimic). Item stock may not: held ≤ cap.
+  if (m.itemPool && gd.raw.items) {
+    for (const [id, rec] of Object.entries(gd.raw.items)) {
+      if (!rec || rec.isGolden) continue;
+      const cap = m.itemPool.cap(id);
+      if (!Number.isInteger(cap)) continue;
+      const h = m.itemPool.held(id);
+      if (h > cap) fail(`item ${id}: held ${h} > cap ${cap}`);
+    }
+  }
+
   // combat fields
   if (m.phase === PHASE.COMBAT) {
     // one field per alive player (+ the force-ended field of a player who quit during this combat)