Preserve timeout and shutdown reasons in question adapters

Author: mchwang

docs/implementation/read-only-review.md

@@ -90,3 +90,5 @@ PR #11 review round 2 confirmed the poll fix and raised an outdated-retry issue
 PR #11 review round 3 reproduced retrying a locally active job after its persisted lease expires (for example after a clock jump). The manager now rejects a retry while that note is in its running map, before touching the persisted attempt. The regression advances wall time without advancing the deadline timer and checks the original attempt, single invocation, and shutdown cancellation remain intact.
 
 PR #11 review round 4 reproduced new question work entering during shutdown. Questions now marks itself closing synchronously before cancelling/draining jobs; start rejects before any store write or agent invocation, during and after shutdown. The regression failed before the guard and checks that the unstarted note has no attempt recorded.
+
+PR #11 round 5 confirmed the shutdown fix and made the timeout-summary concern concrete: the CLI adapter replaced the abort reason with generic cancellation. Direct adapter regressions reproduced this for timeout and shutdown reasons. The adapter now preserves Error-valued abort reasons; provider launch errors remain sanitized.

runner/question-agent.ts

@@ -21,7 +21,7 @@ export function cliQuestionAgent(provider: Provider): QuestionAgent {
         const chunks:Buffer[]=[];let bytes=0,diagnostic='';
         child.stdout.on('data',(chunk:Buffer)=>{bytes+=chunk.length;if(bytes>1024*1024){child.kill('SIGKILL');reject(new Error('Agent output exceeded its limit.'));}else chunks.push(chunk);});
         child.stderr.on('data',(chunk:Buffer)=>{diagnostic=(diagnostic+chunk.toString()).slice(-2000);});
-        child.on('error',error=>reject(new Error(signal.aborted?'Agent cancelled.':`Could not start ${provider}. Check that its CLI is installed and signed in. (${error.name})`)));
+        child.on('error',error=>reject(signal.aborted && signal.reason instanceof Error ? signal.reason : new Error(signal.aborted?'Agent cancelled.':`Could not start ${provider}. Check that its CLI is installed and signed in. (${error.name})`)));
         child.on('close',code=>code===0?resolve(Buffer.concat(chunks).toString('utf8')):reject(new Error(`${provider} exited with status ${code}. Check its login and usage limits.${/auth|login|sign.in/i.test(diagnostic)?' Authentication may be required.':''}`)));
         child.stdin.on('error',()=>{});child.stdin.end(prompt);
       });

test/question-agent.test.ts

@@ -0,0 +1,18 @@
+import { EventEmitter } from 'node:events';
+import { afterEach, expect, it, vi } from 'vitest';
+import { spawn } from 'node:child_process';
+import { cliQuestionAgent } from '../runner/question-agent.ts';
+vi.mock('node:child_process',()=>({spawn:vi.fn()}));
+afterEach(()=>vi.clearAllMocks());
+it.each(['Agent timed out. Try again.','Server stopped. Retry the question.'])('preserves the cancellation reason: %s',async message=>{
+ vi.mocked(spawn).mockImplementation(((_command:unknown,_args:unknown,options:{signal:AbortSignal})=>{
+  const child=Object.assign(new EventEmitter(),{stdout:new EventEmitter(),stderr:new EventEmitter(),stdin:{on:vi.fn(),end:vi.fn()},kill:vi.fn()});
+  options.signal.addEventListener('abort',()=>child.emit('error',new Error('The operation was aborted')),{once:true});
+  return child;
+ }) as unknown as typeof spawn);
+ const controller=new AbortController();const answer=cliQuestionAgent('codex')('Question',controller.signal);
+ const result=answer.catch(error=>error);
+ await vi.waitFor(()=>expect(spawn).toHaveBeenCalledOnce());
+ controller.abort(new Error(message));
+ expect((await result).message).toBe(message);
+});