Add GitHub Actions CI workflow to generated projects

[lbedner]

Summary

Every project generated by aegis init should include GitHub Actions workflow files out of the box so that CI runs automatically on push/PR.

What to include

Workflow: .github/workflows/ci.yml

A single CI workflow triggered on push to main and all PRs that runs:

• Lint (ruff check)
• Type check (ty check or mypy)
• Tests (pytest)
• Format check (ruff format --check)

Considerations

• Use uv for dependency installation (match the project's toolchain)
• Matrix strategy for Python versions if applicable (at minimum the project's target version)
• Cache uv and pip dependencies for faster runs
• The workflow should be a Jinja template so it respects component flags (e.g., only set up PostgreSQL service if include_database is true, only set up Redis if include_redis is true)
• Docker service containers for PostgreSQL and Redis when those components are enabled
• Environment variables from .env.example should be templated in
• Consider a separate deploy.yml later (out of scope for this issue)

Template structure

{{ project_slug }}/.github/workflows/ci.yml.jinja

Example steps

- uses: actions/checkout@v4
- uses: astral-sh/setup-uv@v4
- run: uv sync --all-extras
- run: uv run ruff check .
- run: uv run ruff format --check .
- run: uv run ty check
- run: uv run pytest

Acceptance criteria

• aegis init generates .github/workflows/ci.yml
• Workflow passes on a fresh generated project
• PostgreSQL/Redis service containers are conditionally included based on component flags
• post_gen_tasks.py updated to register/remove the workflow files based on components
• Template tested with make test-template and make test-template-full