Modernize Python packaging and development infrastructure

[Carter Tinney (cartertinney)]

Summary

• make pyproject.toml authoritative for package metadata, dependencies, pytest, Ruff, and Black configuration
• adopt uv for contributor environments, dependency locking, CI setup, and PEP 517 builds
• replace Flake8/Pylint tooling with Ruff while retaining Black formatting and pre-commit hooks
• move the package version to static PEP 621 metadata and read it at runtime through importlib.metadata
• remove obsolete requirements, setup, virtual-environment, build, Bumpversion, and retired release-pipeline files
• update Azure Pipelines to test newest compatible dependencies across Python 3.10-3.14
• modernize the devcontainer and developer setup documentation

The checked-in uv.lock provides a reproducible contributor baseline. CI intentionally runs uv sync --upgrade so this library continues detecting breakage from newly released compatible dependencies.

Validation

• 5,437 unit tests passed on Python 3.10 with upgraded compatible dependencies
• 5,431 unit tests passed and 6 skipped on Python 3.12
• Ruff and Black pre-commit hooks passed
• source distribution and wheel built successfully
• twine check passed for both artifacts
• built wheel installed in a clean environment and reported version 2.15.0rc1
• all Azure Pipelines YAML files parsed successfully
• modernized devcontainer image built successfully
• uv lock --check and git diff --check passed

Stack

This PR is stacked on #1242, which initializes state in a pre-existing E2E test so the newly enabled Ruff gate passes. Review and merge #1242 first. After #1242 merges, this PR should be retargeted to main and updated from main before merging.