Cover Data 0.2.0 under the Python 3.15 Polars wait

[stefan-jansen]

Summary

• extend the existing Polars wait through the 0.2 release line
• record Decision 0015 with unchanged evidence and review triggers
• add regression coverage for accepted 0.2 and rejected 0.3 versions

Verification

• uv run ruff check .
• uv run ruff format --check .
• uv run ty check
• uv run pytest -q (110 passed)
• uv run mkdocs build --strict
• pre-commit run --all-files
• uv run ml4t-ecosystem audit-workspaces --root /home/stefan/ml4t/libraries
• authenticated ecosystem collection: Data passes with source, release, PyPI, and docs at 0.2.0 / 236242844b6a704c78050d18639926e53072d567

Relates #2.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.