Modernize xapi-db-load: migrate to uv, pyproject.toml, PEP 735 dependency groups

[farhan]

Important

PR implemented with the assistance of Claude Code. Refined and validated before being submitted for code review.

Modernize `xapi-db-load`
Part of openedx/public-engineering#506

Summary

• Replace `setup.py`/`setup.cfg` with `pyproject.toml` (PEP 621 static metadata)
• Switch from pip-compile to `uv` with PEP 735 dependency groups; commit `uv.lock`
• Retain pylint/isort/pycodestyle/pydocstyle/mypy as on master.
• Coverage config moved into `pyproject.toml`
• Update CI to use `astral-sh/setup-uv`; SHA-pin all actions

Removed/Updated

Deleted files: `setup.py`, `setup.cfg`, `requirements/`, `.coveragerc`

Updated Makefile targets:

Target	Change
`upgrade`	Replaced pip-compile workflow with `uv run edx_lint write_uv_constraints` + `uv lock --upgrade`
`requirements`	Replaced pip-sync with `uv sync --group dev` + `uv tool install tox --with tox-uv`
`quality`	Replaced `python setup.py bdist_wheel` with `uv run python -m build`

Versioning

`version = "3.1.0"` declared directly in `pyproject.toml` — master had no PyPI publish workflow, so `setuptools-scm` is not used and the version is bumped manually on each release tag.

Important Notes

• This repo does not publish to PyPI, so `src/` layout was not adopted.
• This repo has no PyPI publish workflow on master, so `python-semantic-release` and `release.yml` were not added.
• The `quality` make target has pre-existing pylint failures (unrelated to this migration) — these were present on `main` before this PR.

Testing Notes

This PR has not been manually tested against the repo's own features. Testing relied on CI checks and local agent tooling (`make requirements`, `make lint`, `make test`, `python -m build`). Repo-owner is encouraged to run the repo's feature tests before merging.

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🤖 Generated with Claude Code