feat: upgrade github actions/workflows to `uv` (#453)

* Upgrade GitHub Actions to use uv instead of pip

- Replace actions/setup-python with astral-sh/setup-uv in all workflows
- Update composite actions to use uv commands (uv pip, uv build, etc.)
- Add uv caching with enable-cache: true and uv cache prune --ci
- Add UV_TORCH_BACKEND: cpu for PyTorch installations
- Update cache action to only handle conda caching

* Add activate-environment: true to all astral-sh/setup-uv actions

Explicitly set activate-environment to true for clarity and consistency.

* Fix merge-artifacts job: add setup-uv before using uv commands

* Fix mypy: install types-requests for requests library stubs

* Fix Windows tests: use uv run for pytest to ensure virtual env is used

* Fix package uninstall command: remove -y flag for safer execution

* Fix test command line: use sys.executable for Python calls

* Fix test command line: correct noqa directive for version command

* reverted to original

* Remove complex caching step from CI workflow

* Reorganize uv cache minimization steps in CI workflow

* update placement for mimize caching

* Fix comments and update default age-days for cache cleanup

* Fix working directory for package installation from archive

* Add missing step to minimize uv cache in CI workflow

* re-run

* revert changes

* revert package validation setup to use pip as the standard , (feedback from borda)