fix: resume campaign progress safely

scripts/verify-campaign-settlement-idempotency.mjs

@@ -101,7 +101,71 @@ try {
     'Replaying the exact same victory report must not duplicate gold or items.'
   );
 
-  campaign.completeCampaignAftermath(scenario.id);
+  const aftermathReading =
+    campaign.setCampaignStoryCheckpoint({
+      version: 1,
+      sequenceId:
+        'settlement-aftermath-fixture',
+      beatId: 'settlement-aftermath-fixture',
+      pageIndex: 0
+    });
+  const aftermathReference = {
+    sequenceId:
+      aftermathReading.storyCheckpoint.sequenceId,
+    revision:
+      aftermathReading.storyCheckpoint.revision
+  };
+  const aftermathHandoff =
+    campaign.markCampaignStoryHandoff(
+      aftermathReference.sequenceId,
+      aftermathReference.revision
+    );
+  const beforeMismatchedAftermath =
+    JSON.stringify(aftermathHandoff);
+  const staleAftermath =
+    campaign.completeCampaignStoryHandoffAftermath(
+      scenario.id,
+      {
+        ...aftermathReference,
+        revision:
+          aftermathReference.revision + 1
+      }
+    );
+  assert.equal(
+    JSON.stringify(staleAftermath),
+    beforeMismatchedAftermath,
+    'A stale handoff reference must consume neither the pending aftermath nor its story checkpoint.'
+  );
+  const wrongBattleAftermath =
+    campaign.completeCampaignStoryHandoffAftermath(
+      'second-battle-yellow-turban-pursuit',
+      aftermathReference
+    );
+  assert.equal(
+    JSON.stringify(wrongBattleAftermath),
+    beforeMismatchedAftermath,
+    'A mismatched battle must consume neither half of an aftermath handoff.'
+  );
+  const completedAftermath =
+    campaign.completeCampaignStoryHandoffAftermath(
+      scenario.id,
+      aftermathReference
+    );
+  assert.equal(
+    completedAftermath.pendingAftermathBattleId,
+    undefined,
+    'An exact aftermath handoff must retire the pending settlement.'
+  );
+  assert.equal(
+    completedAftermath.storyCheckpoint,
+    undefined,
+    'An exact aftermath handoff must retire its story checkpoint atomically.'
+  );
+  assert.equal(
+    completedAftermath.storyCheckpointRevision,
+    aftermathReference.revision + 1,
+    'An exact aftermath handoff must invalidate its consumed revision.'
+  );
   campaign.setActiveCampVisitId(
     'first-pursuit-scout-tent'
   );