Add Codex Review pipeline

Author: dbabokin

.github/workflows/codex-pr-review.yml

@@ -0,0 +1,46 @@
+# Copyright 2025, Intel Corporation
+# SPDX-License-Identifier: BSD-3-Clause
+name: Codex PR Review
+
+# This workflow does one simple thing - it posts a comment "@codex review" under the name of the person who has
+# active OpenAI ChatGPT subscription with Codex integration to this repo enabled. This triggers Codex review.
+
+# To update the token:
+# If you have ChatGPT subscription, go to https://chatgpt.com/codex and Click "Enable Code Review".
+# After that create your personal (scoped) Github token for ispc org with
+# Pull Request and Issues "read and write" permissions and store that token in
+# CODEX_TOKEN ispc github org secrets.
+
+on:
+  pull_request:
+    types: [opened, reopened]
+  workflow_dispatch:  # Manual trigger
+    inputs:
+      pr_number:
+        description: 'PR number to comment on'
+        required: true
+        type: number
+
+jobs:
+  comment:
+    runs-on: ubuntu-latest
+    # The secret is available only in that repo.
+    if: github.repository == 'ispc/ispc'
+    steps:
+      - name: Comment on PR
+        uses: actions/github-script@v8
+        with:
+          github-token: ${{ secrets.CODEX_TOKEN }}
+          script: |
+            const pr_number = parseInt(
+              context.eventName === 'workflow_dispatch'
+                ? context.payload.inputs.pr_number
+                : context.issue.number
+            );
+
+            await github.rest.issues.createComment({
+              issue_number: pr_number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: '@codex review'
+            });