ci: merge-candidate compares patch-ids without the review documents

The candidate is the branch tip, which already carries the round's
CODE-REVIEW-N-rK.md; the material the reviewer read does not. With
docs/reviews in the diff the two patch-ids never matched once dev had
moved, so every green candidate went back to review whenever another
task published its own document in the meantime — #514 looped twice on
09.09 and #508 only merged when dev happened to stand still. The
patch-id now excludes docs/reviews, exactly like `reviewedFresh` next to
it; a real change of the patch under rebase still returns the task.

Mutant: merge-rereviews-own-review-doc.

Issue: #516
User-Visible: no

test/merge-candidate.test.mjs

@@ -1,7 +1,7 @@
 import test from 'node:test';
 import assert from 'node:assert/strict';
 import { execFileSync, spawnSync } from 'node:child_process';
-import { mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { join } from 'node:path';
 
@@ -265,3 +265,65 @@ test('#510 r2 M1: realOps.waitValidate with only a cancelled dispatch reports mi
   const r = await ops.waitValidate('c'.repeat(40), { event: 'workflow_dispatch' });
   assert.equal(r.result, 'missing');
 });
+
+// ---------- #516: the candidate carries its own review document; dev moves by other documents ----------
+
+test('#516 AC1: dev moved only by review documents and the branch carries its own — patch-id equal, merge goes through Validate, not re-review', async () => {
+  const dir = mkdtempSync(join(tmpdir(), 'hp-merge-516-'));
+  try {
+    const origin = join(dir, 'origin.git');
+    const work = join(dir, 'work');
+    execFileSync('git', ['init', '-q', '--bare', origin]);
+    execFileSync('git', ['clone', '-q', origin, work]);
+    const cfg = ['-c', 'user.name=t', '-c', 'user.email=t@x'];
+    const git = (cwd, ...args) => execFileSync('git', ['-C', cwd, ...cfg, ...args], { encoding: 'utf8' }).trim();
+    const commit = (msg) => execFileSync('git', ['-C', work, ...cfg, 'commit', '-q', '-am', msg]);
+    mkdirSync(join(work, 'docs', 'reviews'), { recursive: true });
+    writeFileSync(join(work, 'a.mjs'), 'export const a = 20;\n');
+    writeFileSync(join(work, 'docs', 'reviews', '.keep'), '');
+    git(work, 'add', '.');
+    commit('base');
+    git(work, 'branch', '-M', 'dev');
+    git(work, 'push', '-q', '-u', 'origin', 'dev');
+    // ветка задачи: код + (позже) её собственный документ ревью
+    git(work, 'checkout', '-q', '-b', 'issue/9-fix');
+    writeFileSync(join(work, 'a.mjs'), 'export const a = 21;\n');
+    commit('fix');
+    const material = git(work, 'rev-parse', 'HEAD');
+    writeFileSync(join(work, 'docs', 'reviews', 'CODE-REVIEW-9-r1.md'), '# CODE-REVIEW-9-r1\nVerdict: green\n');
+    git(work, 'add', '.');
+    commit('docs: review document for #9');
+    git(work, 'push', '-q', '-u', 'origin', 'issue/9-fix');
+    // dev двинулся чужим документом ревью — ровно то, что делает каждый паблиш конвейера
+    git(work, 'checkout', '-q', 'dev');
+    writeFileSync(join(work, 'docs', 'reviews', 'CODE-REVIEW-8-r2.md'), '# CODE-REVIEW-8-r2\n');
+    git(work, 'add', '.');
+    commit('docs: review document for #8');
+    git(work, 'push', '-q', 'origin', 'dev');
+
+    const calls = [];
+    const ops = realOps({ repo: 'x/y', token: 'none' });
+    ops.pushWithLease = (sha, ref, expected) => {
+      calls.push(['push', ref, expected]);
+      const r = spawnSync('git', ['-C', work, 'push', '-q', `--force-with-lease=refs/heads/${ref}:${expected}`, 'origin', `${sha}:refs/heads/${ref}`], { encoding: 'utf8' });
+      return r.status === 0;
+    };
+    ops.dispatchValidate = (ref) => { calls.push(['dispatch', ref]); };
+    ops.waitValidate = async (sha) => { calls.push(['validate', sha]); return { result: 'green', url: 'https://run/1' }; };
+    ops.comment = (issue, body) => { calls.push(['comment', body.slice(0, 60)]); };
+    ops.log = () => {};
+    const inWork = (fn) => (...args) => { const cwd = process.cwd(); process.chdir(work); try { return fn(...args); } finally { process.chdir(cwd); } };
+    for (const name of ['fetch', 'revParse', 'mergeBase', 'diffNames', 'patchId', 'rebaseOnto']) ops[name] = inWork(ops[name]);
+
+    const r = await mergeCandidate({ branch: 'issue/9-fix', material, issue: 9, ops });
+    assert.equal(r.action, 'push', JSON.stringify(calls));
+    assert.ok(calls.some((c) => c[0] === 'validate'), 'кандидат прошёл Validate');
+    assert.ok(!calls.some((c) => c[0] === 'comment' && /patch-id/.test(c[1])), 'нет возврата «дифф изменился»');
+    const devTip = git(work, 'rev-parse', 'origin/dev');
+    assert.match(git(work, 'show', `${devTip}:a.mjs`), /a = 21/);
+    assert.equal(git(work, 'cat-file', '-t', `${devTip}:docs/reviews/CODE-REVIEW-9-r1.md`), 'blob', 'документ раунда уехал вместе с кодом');
+    assert.equal(git(work, 'cat-file', '-t', `${devTip}:docs/reviews/CODE-REVIEW-8-r2.md`), 'blob');
+  } finally {
+    rmSync(dir, { recursive: true, force: true });
+  }
+});