Watching a teammate shows their hand, 临时整备区, equipment, strategy and effects (#129)

The prep scout of another player's board carries their 整备区 hand and 临时整备区 as units on the bench rows (like the own prep bench), the equipped items of their operators, their strategy in the drawer and their effects column (the official mode shows a teammate's hand too). The scout signature includes the hand / temp slots, so a moved card refreshes the watcher. Closes #128. Contributed by @2321Robin.

public/js/battle/observe.js

@@ -9,6 +9,7 @@
 //   * eliminated: anything.
 
 import { PHASE } from '../../../shared/constants.js';
+import { data } from '../data.js';
 
 const isObj = (v) => !!v && typeof v === 'object';
 const COMBAT = new Set([PHASE.COMBAT, PHASE.UNITE, PHASE.FINAL_ASSAULT, PHASE.HIDDEN_CORE]);
@@ -130,3 +131,32 @@ export function layerCamera(field, layer, mySide = 'L') {
   if (layer === 'L' || layer === 'R') return { rect, side: layer, half: true };
   return { rect, side: mySide };
 }
+
+/**
+ * The watched player's effects column for a battle watched as a display replica (user playtest #2: while spectating,
+ * the right column shows the spectated player's effects, not one's own). The spec's raw playerEffects (Battle spec:
+ * `{ id, source = iconKind, counter, … }`) resolved client-side — a band effect through bands.json (its effectId),
+ * everything else through effects.json; `effectIconUrl`'s per-kind fallbacks cover the missing icon ids. Undefined
+ * where whose column would be ambiguous (联防 / boss pairs) or there are no effects data (a server-run field's meta
+ * comes from the server without effects — the column stays empty rather than showing one's own).
+ */
+export function spectateEffects(spec, members) {
+  if (!Array.isArray(members) || members.length !== 1 || !isObj(spec)) return undefined;
+  const p = Array.isArray(spec.players) ? spec.players.find((x) => isObj(x) && x.playerId === members[0]) : null;
+  if (!p || !Array.isArray(p.playerEffects)) return undefined;
+  const out = [];
+  for (const pe of p.playerEffects) {
+    if (!isObj(pe) || typeof pe.id !== 'string' || !pe.id) continue;
+    const counter = pe.counter != null ? { counter: pe.counter } : {};
+    if (pe.source === 'band') {
+      const band = data.list('bands').find((b) => b && b.effectId === pe.id);
+      if (band) {
+        out.push({ id: pe.id, name: band.effectName || band.name, desc: band.desc || '', iconKind: 'band', iconId: band.iconId || band.bandId, ...counter });
+        continue;
+      }
+    }
+    const rec = data.lookup('effects', pe.id);
+    out.push({ id: pe.id, name: rec?.name || pe.id, desc: rec?.desc || rec?.descRaw || '', iconKind: pe.source || 'choice', iconId: pe.id, ...counter });
+  }
+  return out;
+}