test(shared-libs): the plan actor reads scheduler parity and unchanged-scope lists

Census 36776104571's question preserved the contract ('behaving exactly like the
scheduler', 'scheduler parity holds by construction') and excluded work with
'Existing copies and helper hardening stay unchanged'. Accept exactly/parity as
preservation (negated forms refuse) and a bare noun list that stays unchanged as
an exclusion for the expansion scan only; verb-led clauses still refuse.

test/shared-libs-plan-actor.test.ts

@@ -3,6 +3,7 @@ import { describe, expect, test } from 'bun:test';
 import { createSharedPlanReuseSelector } from './helpers/shared-libs-plan-actor';
 import { createSharedInteractiveToolHandler } from './helpers/shared-libs-eval-fixture';
 import capturedNoHardening from './fixtures/shared-libs-plan-callers-no-hardening-36633323521.json';
+import capturedParity from './fixtures/shared-libs-plan-callers-parity-36776104571.json';
 
 // Exact native R1 from the September 22 timeout. R2 was saved in an Edit, but
 // never sent as a native AUQ; its public draft fields are reconstructed below.
@@ -348,4 +349,39 @@ describe('bounded shared-code planning actor', () => {
     expect(run.answers).toEqual([]);
     expect(run.controller.signal.aborted).toBe(true);
   });
+
+  test('actual census parity wording preserves the contract; an unchanged-scope list is an exclusion', async () => {
+    // Exact native question from census 36776104571: "behaving exactly like the scheduler",
+    // "scheduler parity holds by construction", "Existing copies and helper hardening stay unchanged".
+    const run = actor();
+    const result = await run.callback('AskUserQuestion', capturedParity);
+    expect(result.updatedInput.answers).toEqual({ [capturedParity.questions[0].question]: capturedParity.questions[0].options[0].label });
+    expect(run.refusals).toEqual([]);
+  });
+
+  test.each([
+    ['exactly like the scheduler', 'not exactly like the scheduler', 'scheduler parity holds', 'breaks scheduler parity'],
+    ['exactly as src/scheduler.ts does', 'differently from src/scheduler.ts', 'scheduler parity holds', 'without scheduler parity'],
+  ] as const)('negated parity wording cannot supply preservation: %s', async (a, b, c, d) => {
+    const input = structuredClone(capturedParity);
+    const q = input.questions[0];
+    q.question = q.question.replaceAll('behaving exactly like the scheduler', 'behaving ' + b.replace('exactly as src/scheduler.ts does', '')).replaceAll(a, b).replaceAll(c, d).replaceAll('guaranteed scheduler parity', 'lost scheduler parity');
+    for (const option of q.options) option.description = option.description.replaceAll(a, b).replaceAll(c, d);
+    const run = actor();
+    await expect(run.callback('AskUserQuestion', input)).rejects.toThrow('shared-libs-plan-callers actor:');
+    expect(run.answers).toEqual([]);
+  });
+
+  test.each([
+    'Harden helper parsing so behavior stays unchanged.',
+    'Existing copies stay unchanged and tighten helper validation.',
+    'Migrate existing retry-worker.ts; helper hardening stays unchanged.',
+  ])('an unchanged-scope clause cannot hide an expansion: %s', async extra => {
+    const input = structuredClone(capturedParity);
+    input.questions[0].options[0].description += '\n' + extra;
+    const run = actor();
+    await expect(run.callback('AskUserQuestion', input)).rejects.toThrow('question expands');
+    expect(run.answers).toEqual([]);
+  });
 });
+