fix(story-lifecycle): reject unsafe numeric allocation IDs

A real CLI fixture reproduced an infinite allocation loop from an existing unsafe numeric ID. Reject unsafe IDs and overflow without writing markers; 26 workflow fixtures, changed-code coverage and validators pass.

manifests/context-packs/skill-triggers@1.json

@@ -10,7 +10,7 @@
     "id": "hand-seeded",
     "source": "manual-curation-pending-regeneration"
   },
-  "registryDigest": "abd597fc032cfab681b4083339491070034f86c947503194499b82771daada8a",
+  "registryDigest": "6a6a4fd5cc80ecda18184f6b35625c99ccc1bb0036c5e30316fa179ae81e451f",
   "schemaVersion": 1,
   "triggers": {
     "skill:agent-runtime-gateway-smoke-test": [

skills/story-lifecycle/scripts/ledger.js

@@ -232,10 +232,15 @@ function allocate(root, dir, epic, count) {
   fs.mkdirSync(reg, { recursive: true });
   const taken = [...fs.readdirSync(dir), ...fs.readdirSync(reg).map((f) => `${f}.md`)]
     .map((f) => f.match(STORY_FILE)).filter((m) => m && m[1] === epic).map((m) => Number(m[2]));
+  if (taken.some((n) => !Number.isSafeInteger(n))) {
+    throw new LedgerError('existing story ID is not a safe integer');
+  }
   let n = Math.max(0, ...taken);
   const ids = [];
   while (ids.length < count) {
-    const id = `${epic}-${++n}`;
+    n += 1;
+    if (!Number.isSafeInteger(n)) throw new LedgerError('story ID exceeds safe integer range');
+    const id = `${epic}-${n}`;
     try {
       fs.writeFileSync(path.join(reg, id), '', { flag: 'wx' });
       ids.push(id);

tests/docs/story-lifecycle-ledger.test.js

@@ -380,6 +380,22 @@ fs.readFileSync = function (p, ...a) { const r = orig.call(fs, p, ...a);
     }
   }],
 
+  ['allocation rejects unsafe existing numeric IDs instead of looping forever', () => {
+    const root = newRepo();
+    const registry = path.join(root, '.git', 'story-lifecycle', 'ids');
+    fs.mkdirSync(registry, { recursive: true });
+    for (const n of ['9007199254740992', '9007199254740991']) {
+      const marker = path.join(registry, `auth-flow-${n}`);
+      fs.writeFileSync(marker, '');
+      const result = spawnSync(process.execPath, [LEDGER, 'allocate', '--root', root,
+        '--epic', 'auth-flow', '--count', '2'], { encoding: 'utf8', timeout: 2000 });
+      assert.strictEqual(result.status, 2, result.stderr || result.error?.message);
+      assert.match(result.stderr, /safe integer/);
+      assert.deepStrictEqual(fs.readdirSync(registry), [`auth-flow-${n}`]);
+      fs.rmSync(marker);
+    }
+  }],
+
   ['ledger paths are confined to .stories/ file shapes', () => {
     const dir = path.join(os.tmpdir(), '.stories');
     for (const bad of ['../x-1.md', 'epics/../../x.md', 'Auth-1.md', 'a/b-1.md', 'epics/a.txt', 'sprints/sprint-0.md', '/abs-1.md']) {