[keertip]

Adds a standalone script (tool/build_codex_plugin.dart) and GitHub Actions workflow (.github/workflows/release_codex_plugin.yaml) to build and package the dart-flutter Codex plugin zip for the OpenAI plugin submission portal.

What this changes

• tool/build_codex_plugin.dart: A self-contained Dart script (using only dart:io and dart:convert, with no new pubspec.yaml dependencies) that:
  • Validates the repo manifest and packaging inputs (semver version matching --tag, interface.shortDescription <= 30 characters, existing branding assets, and tracked skills/<skill>/SKILL.md directories).
  • Generates a skills-only release copy of .codex-plugin/plugin.json in a temporary staging directory with mcpServers and MCP references removed (since OpenAI only accepts local stdio MCP servers from allowlisted partners) and sets extensions.com.openai.publication.release_notes from skill changes since the previous codex-plugin-v* tag.
  • Stages only Git-tracked files under skills/ (git ls-files) plus the referenced branding assets and builds dist/<name>-codex-<version>.zip.
  • Supports --release (and --release --dry-run) to verify a clean main branch, create and push the codex-plugin-v<version> tag, wait for the CI workflow run via gh, and download the built zip artifact to dist/.
• .github/workflows/release_codex_plugin.yaml:
  • Runs on codex-plugin-v* tags, workflow_dispatch, and pull requests touching .codex-plugin/, assets/, skills/, or tool/build_codex_plugin.dart.
  • Checks formatting (dart format), runs static analysis (dart analyze --fatal-infos), and builds the release zip.
  • Uploads dart-flutter-codex-<version>.zip as a workflow artifact (30-day retention) on tag and manual runs.
  • Opens a GitHub issue labeled codex-release if a tag-triggered release build fails.
• .gitignore: Ignores dist/.

[gemini-code-assist]

Code Review

This pull request introduces a new Dart script at tool/build_codex_plugin.dart to automate building, verifying, and releasing the Dart and Flutter Codex plugin zip, while updating .gitignore to exclude the dist/ directory. The review feedback focuses on enhancing the script's robustness and concurrency. It is recommended to wrap external process executions (zip, gh, and git) in try-catch blocks to gracefully handle ProcessException when these command-line tools are not installed. Additionally, the synchronous Process.runSync call within the asynchronous polling loop of _waitForRun should be replaced with the asynchronous Process.run to avoid blocking the Dart event loop.