fix(paired): stop silent halt on reviewer PROCEED + reviewer-unavailable

Two causes of the paired room "keeps stopping" symptom:
- Reviewer approvals worded as "PROCEED" were parsed as 'continue'
  (a change request), causing an owner TASK_DONE <-> reviewer PROCEED
  ping-pong until the deadlock cap. parseReviewerVerdict() now treats a
  leading PROCEED as approval so the turn finalizes after one round.
- When the Codex reviewer was unavailable, the owner's answer was held
  for review and the user saw nothing. Now the held owner answer is
  emitted with a "review skipped" notice on reviewer_codex_unavailable.

Verified: tsc --noEmit clean; 27 related vitest tests pass.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/paired-verdict.test.ts

@@ -2,7 +2,9 @@ import { describe, expect, it } from 'vitest';
 
 import {
   classifyArbiterVerdict,
+  parseReviewerVerdict,
   parseVisibleVerdict,
+  stripLeadingStatusLine,
 } from './paired-verdict.js';
 
 describe('paired verdict parser', () => {
@@ -80,6 +82,45 @@ describe('paired verdict parser', () => {
     ).toBe('continue');
   });
 
+  it('treats a reviewer PROCEED line as an approval (DONE)', () => {
+    expect(parseReviewerVerdict('PROCEED\n위치와 첨부는 맞습니다.')).toBe('done');
+    expect(parseReviewerVerdict('**PROCEED**\n최종 답변 내용 맞습니다.')).toBe(
+      'done',
+    );
+    expect(
+      parseReviewerVerdict(
+        ['검토 결과를 정리합니다.', 'PROCEED', '확정합니다.'].join('\n'),
+      ),
+    ).toBe('done');
+  });
+
+  it('does not upgrade non-approval reviewer verdicts', () => {
+    // REVISE / RESET / plain prose remain a change request ('continue').
+    expect(parseReviewerVerdict('REVISE\n이 부분을 고쳐주세요')).toBe('continue');
+    expect(parseReviewerVerdict('RESET\n방향을 다시 잡읍시다')).toBe('continue');
+    expect(parseReviewerVerdict('추가 수정이 필요합니다')).toBe('continue');
+    // Documented reviewer tokens still parse to their own verdicts.
+    expect(parseReviewerVerdict('TASK_DONE\n승인합니다')).toBe('task_done');
+    expect(parseReviewerVerdict('DONE_WITH_CONCERNS\n우려가 있습니다')).toBe(
+      'done_with_concerns',
+    );
+    // "PROCEED" mentioned in prose, not as the leading verdict, is ignored.
+    expect(
+      parseReviewerVerdict('리뷰어가 PROCEED 했는지 확인이 필요합니다'),
+    ).toBe('continue');
+  });
+
+  it('strips a leading status line for direct delivery', () => {
+    expect(stripLeadingStatusLine('TASK_DONE\n\n실제 답변입니다.')).toBe(
+      '실제 답변입니다.',
+    );
+    expect(stripLeadingStatusLine('STEP_DONE\n다음 내용')).toBe('다음 내용');
+    // No leading status token → text is returned untouched.
+    expect(stripLeadingStatusLine('그냥 본문입니다.\n둘째 줄')).toBe(
+      '그냥 본문입니다.\n둘째 줄',
+    );
+  });
+
   it('classifies arbiter verdicts from leading visible lines', () => {
     expect(classifyArbiterVerdict('PROCEED\ncontinue')).toBe('proceed');
     expect(classifyArbiterVerdict('**VERDICT: REVISE**\nfix it')).toBe(