Connect bounded arrival overlap and Fremen Nexus movement Betrayal

game/arrival-overlap.ts

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+import type { Game } from './engine';
+
+type Overlap = NonNullable<Game['pendingArrivalOverlap']>;
+type TerrorEntry = NonNullable<Game['pendingTerrorEntry']>;
+
+/** The immutable trigger, not later owner choices or child stages. */
+export function arrivalOverlapSignature(record: Overlap): string {
+  return JSON.stringify([record.event, record.turn, record.phase, record.entrant,
+    record.territory, record.sector, record.amount, record.elite, record.cause,
+    record.resume, record.ecaz, record.moritani, record.first,
+    record.ambassadorToken, record.terrorTokens]);
+}
+
+/** The overlap owns the worm return while either serialized Terror prompt is live. */
+export function overlapOwnsWormTerror(
+  g: Pick<Game, 'pendingArrivalOverlap' | 'turn' | 'phase'>,
+  entry: Pick<TerrorEntry, 'cause' | 'resume' | 'entrant' | 'territory' |
+    'sector' | 'amount' | 'elite' | 'turn' | 'phase' | 'token'>,
+): boolean {
+  const overlap = g.pendingArrivalOverlap;
+  return !!overlap && overlap.signature === arrivalOverlapSignature(overlap) &&
+    overlap.resume === 'wormRide' && overlap.cause === 'wormRide' &&
+    entry.cause === 'wormRide' && entry.resume === 'none' &&
+    overlap.turn === g.turn && overlap.phase === g.phase &&
+    entry.turn === overlap.turn && entry.phase === overlap.phase &&
+    entry.entrant === overlap.entrant && entry.territory === overlap.territory &&
+    entry.sector === overlap.sector && entry.amount === overlap.amount &&
+    entry.elite === overlap.elite && overlap.terrorTokens.includes(entry.token) &&
+    ((overlap.first === 'terror' && overlap.stage === 'first') ||
+      (overlap.first === 'ambassador' && overlap.stage === 'second'));
+}