Allow Advanced Auditor inspection choice

game/choam-auditor.ts

@@ -55,23 +55,37 @@ export function auditCount(
   );
 }
 
+/** Validate the holder's chosen size against the actual eligible maximum.
+ * An omitted choice preserves the legacy maximum, including an empty audit. */
+export function selectedAuditCount(maximum: number, selectedCount?: number): number {
+  if (!Number.isInteger(maximum) || maximum < 0 || maximum > 2)
+    throw new Error('Auditor requires a valid inspection maximum.');
+  if (selectedCount === undefined) return maximum;
+  if (!Number.isInteger(selectedCount) || selectedCount < 1 || selectedCount > maximum)
+    throw new Error('Auditor inspection count must be between one and the eligible maximum.');
+  return selectedCount;
+}
+
 /**
  * Call once after the engine resolves cancellation/payment, and persist the
  * resulting private snapshot. A read or projection must never call this helper.
  * Partial Fisher-Yates samples physical cards uniformly without replacement.
  * Selecting the entire eligible pool consumes no randomness.
+ * Omit selectedCount for the legacy maximum; a supplied count must be at
+ * least one and no greater than the current eligible inspection maximum.
  */
 export function sampleAuditCards(
   hand: readonly Card[],
   usedIds: readonly string[],
   survived: boolean,
   random: () => number,
+  selectedCount?: number,
 ): Card[] {
   const limit = inspectionLimit(survived);
   const eligible = auditCandidates(hand, usedIds);
   if (typeof random !== 'function')
     throw new Error('Auditor requires a server-supplied random source.');
-  const count = Math.min(limit, eligible.length);
+  const count = selectedAuditCount(Math.min(limit, eligible.length), selectedCount);
   if (count === eligible.length) return eligible;
   for (let i = 0; i < count; i++) {
     const draw = random();