feat: use uv as package manager, ruff as linter, add github actions

[ymarcon]

No description provided.

[Copilot]

Pull request overview

This PR migrates the Python project from Poetry to a uv + hatchling toolchain, adds Ruff for linting/formatting, and introduces GitHub Actions workflows for CI, deployment, and stale issue management.

Changes:

• Replace Poetry configuration/lockfile with PEP 621 pyproject.toml, uv.lock, and hatchling build backend.
• Add Ruff configuration and wire lint/format into Makefile and CI.
• Add GitHub Actions workflows for CI, tag-based publish, and stale issues; update tests and implementation formatting/error handling.

Reviewed changes

Copilot reviewed 11 out of 14 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
uv.lock	Adds uv lockfile to pin dependency resolution.
pyproject.toml	Migrates project metadata/deps to PEP 621 and switches build backend to hatchling.
poetry.lock	Removes Poetry lockfile as part of the migration.
Makefile	Updates local workflows to use uv + ruff and adds build/install targets.
.ruff.toml	Introduces Ruff lint/format configuration.
.gitignore	Expands ignored local/dev artifacts (e.g., .venv/, debug files).
datashield_opal/impl.py	Refactors Opal driver implementation (formatting, error chaining, small logic changes).
datashield_opal/__init__.py	Minor export adjustment for OpalDriver.
tests/test_impl.py	Test refactors (style/assertions, improved exception assertions).
tests/test_api_analysis.py	Refactors tests and adds error handling around API calls.
tests/test_api_admin.py	Refactors tests for style consistency.
.github/workflows/ci.yml	Adds CI to install with uv, run Ruff, and run pytest across Python versions.
.github/workflows/deploy.yml	Adds tag-triggered build + publish workflow using uv.
.github/workflows/stale.yml	Adds automation to mark/close stale issues.

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