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.

public/js/ui/fieldHost.js

@@ -268,31 +268,46 @@ export async function mountFieldView(host, { signal } = {}) {
  */
 export function useFieldView(hostRef) {
   const [state, setState] = useState({ view: null, kind: 'loading' });
+  const [attempt, setAttempt] = useState(0);
+  const retries = useRef(0);
   const viewRef = useRef(null);
   useEffect(() => {
-    let dead = false;
+    let dead = false, retrying = false;
     const host = hostRef.current;
     if (!host) return undefined;
+    setState({ view: null, kind: 'loading' });
     const controller = new AbortController();
     mountFieldView(host, { signal: controller.signal }).then((view) => {
       if (dead) { view.destroy(); return; }
       viewRef.current = view;
+      if (view.kind === 'engine') retries.current = 0;
       globalThis.__SP_VIEW__ = view; // dev / E2E introspection (view.raw.stats?.())
       setState({ view, kind: view.kind });
     }, (err) => { if (!dead && !controller.signal.aborted) console.error('[field] mount failed', err); });
     const unsub = settingsStore.subscribe((s) => viewRef.current?.setSettings?.(s));
     const onResize = () => viewRef.current?.resize();
+    // A temporary network/vendor failure must not pin this mounted match to fallback forever. Retry on a useful
+    // user event, at most twice in succession; the effect cleanup disposes the old view before creating its successor.
+    const onRetry = () => {
+      if (dead || retrying || viewRef.current?.kind !== 'fallback' || renderPref() === 'fallback'
+        || document.visibilityState !== 'visible' || globalThis.navigator?.onLine === false || retries.current >= 2) return;
+      retrying = true; retries.current++; setAttempt((n) => n + 1);
+    };
     window.addEventListener('resize', onResize);
+    window.addEventListener('online', onRetry);
+    document.addEventListener('visibilitychange', onRetry);
     return () => {
       dead = true;
       controller.abort();
       unsub();
       window.removeEventListener('resize', onResize);
+      window.removeEventListener('online', onRetry);
+      document.removeEventListener('visibilitychange', onRetry);
       // the dev hook must not keep the destroyed view — and through its host the whole detached match screen — alive
       if (viewRef.current && globalThis.__SP_VIEW__ === viewRef.current) globalThis.__SP_VIEW__ = null;
       viewRef.current?.destroy();
       viewRef.current = null;
     };
-  }, []);
+  }, [attempt]);
   return state;
 }