test: close session preparation CI gaps

packages/subagent/subagent/tests/continuation.spec.ts

@@ -568,6 +568,17 @@ describe('SubagentService.followup residency routing', () => {
       .rejects.toMatchObject({ code: 'NOT_RESUMABLE' })
   })
 
+  it('preserves a SubagentError raised while cold-materializing a child', async () => {
+    const { ctx, parent } = await setup([textResponse('first')])
+    const started = await ctx.subagents.startContinuable(startSpec(parent))
+    await waitNoActivation(ctx, started.childId)
+    const failure = new SubagentError('materialization denied', 'UNAUTHORIZED')
+    ctx.agents.resume = () => Promise.reject(failure)
+
+    await expect(followup(ctx, parent, started.childId, message('continue')))
+      .rejects.toBe(failure)
+  })
+
   it('cold-resumes a delivery that lost the race with final disposal', async () => {
     const { ctx, parent } = await setup([textResponse('first'), textResponse('after the race')])
     const started = await ctx.subagents.startContinuable(startSpec(parent))

packages/subagent/subagent/tests/list-children.spec.ts

@@ -363,6 +363,17 @@ describe('SubagentService.listChildren', () => {
     expect(entries).toEqual([{ kind: 'diagnostic', id: childId, reason: 'unavailable' }])
   })
 
+  it('maps an invalid child surface to corrupt', async () => {
+    const { ctx, parent } = await setup([textResponse('done')])
+    const childId = await startChild(ctx, parent, 'invalid surface')
+    const query = ctx.get('sessionQuery')!
+    query.listEvents = () =>
+      Promise.reject(new SessionQueryError('invalid surface', 'SESSION_QUERY_INVALID_SURFACE'))
+
+    const entries = await ctx.subagents.listChildren(parent.id)
+    expect(entries).toEqual([{ kind: 'diagnostic', id: childId, reason: 'corrupt' }])
+  })
+
   it('diagnoses a read whose header no longer names this parent as corrupt', async () => {
     const { ctx, parent } = await setup([textResponse('done')])
     const childId = await startChild(ctx, parent, 'reparented child')