Advanced AI Prompt for Python Poetry and FastAPI Automation

Act as a Principal Cloud Architect specializing in Python CI/CD. Generate a robust GitHub Actions workflow for a FastAPI application named [APP_NAME] utilizing Poetry for dependency management. The workflow must: 1) Implement a `strategy: matrix` to concurrently test against multiple Python versions, including [PYTHON_VERSION]. 2) Implement aggressive caching for the Poetry installation and the `.venv` directory to minimize build minutes. 3) Execute Pytest and Flake8 within the virtual environment. 4) Upon successful matrix completion, package the artifact and prepare an automated deployment hook to [CLOUD_PROVIDER]. Explicitly utilize the `concurrency` key to automatically cancel redundant outdated runs on the same PR branch.