fix(github): retain labels in issue indexes

packages/github/src/__tests__/emit-auxiliary-files.test.ts

@@ -425,11 +425,48 @@ describe('emitGitHubAuxiliaryFiles', () => {
     );
     assert.equal(client.files.get(githubByStateAliasPath('acme', 'widgets', 'issues', 'open', 7)), canonicalBytes);
     assert.equal(client.files.get(githubByEditedAliasPath('acme', 'widgets', 'issues', '2026-05-12', 7)), canonicalBytes);
+    const issueRows = JSON.parse(client.files.get(indexPath) ?? '[]') as Array<Record<string, unknown>>;
+    assert.deepEqual(issueRows, [
+      {
+        id: '7',
+        title: 'Bug report',
+        updated: '2026-05-12T00:00:00Z',
+        number: 7,
+        state: 'open',
+        labels: ['P0 Critical'],
+        assigneeKeys: ['octocat'],
+        creatorKey: 'monalisa',
+        priority: 'P0 Critical',
+      },
+    ]);
 
     // No writes leaked into the pulls index for this repo.
     assert.ok(!writtenPaths.includes(githubRepoPullsIndexPath('acme', 'widgets')));
   });
 
+  it('retains an explicit empty label array in issue index rows', async () => {
+    const client = createClient();
+    await emitGitHubAuxiliaryFiles(client, {
+      workspaceId: 'ws-1',
+      issues: [
+        {
+          owner: 'acme',
+          repo: 'widgets',
+          number: 8,
+          title: 'Unlabeled issue',
+          state: 'open',
+          labels: [],
+          updated_at: '2026-05-13T00:00:00Z',
+        },
+      ],
+    });
+
+    const rows = JSON.parse(client.files.get(githubRepoIssuesIndexPath('acme', 'widgets')) ?? '[]') as Array<
+      Record<string, unknown>
+    >;
+    assert.deepEqual(rows[0]?.labels, []);
+  });
+
   it('uses the newest lifecycle timestamp for PR by-edited aliases', async () => {
     const client = createClient();
 

packages/github/src/emit-auxiliary-files.ts

@@ -780,6 +780,7 @@ function buildRecordIndexRow(
     updated: readLifecycleEditedAt(record) ?? readUpdatedAt(record),
     number: Number(number),
     state: state ?? '',
+    labels: readGitHubLabelNames(record),
     ...withOptionalArray('assigneeKeys', readGitHubAssigneeKeys(record)),
     ...withOptionalString('creatorKey', readGitHubCreatorKey(record)),
     ...withOptionalString('priority', readPriority(record)),
@@ -974,6 +975,15 @@ function readGitHubAssigneeKeys(record: Record<string, unknown>): string[] {
   return uniqueStrings(assignees.map((entry) => readUserKey(entry)).filter((entry): entry is string => Boolean(entry)));
 }
 
+function readGitHubLabelNames(record: Record<string, unknown>): string[] {
+  const labels = Array.isArray(record.labels) ? record.labels : [];
+  return uniqueStrings(
+    labels
+      .map((label) => readNonEmptyString(label) ?? readNonEmptyString(isRecord(label) ? label.name : undefined))
+      .filter((label): label is string => Boolean(label)),
+  );
+}
+
 function readGitHubCreatorKey(record: Record<string, unknown>): string | undefined {
   return readUserKey(record.user) ?? readNonEmptyString(record.user);
 }