fix: prepare prerelease packages for PyPI

[Volv-G]

Summary

• add the tangle-cli console-script alias while keeping tangle canonical
• prepare a safer prerelease package shape with both tangle-cli and tangle-api at 0.0.1a2
• pin tangle-cli[native] to tangle-api==0.0.1a2 and tangle-api back to tangle-cli==0.0.1a2 for the short-term circular release
• update the PyPI release workflow to build, smoke-test, and publish both packages
• add a local packages/tangle-api/README.md so uv build --package tangle-api succeeds for sdist+wheel builds

Checks

• git diff --check origin/master
• uv run pytest (621 passed)
• uv run pytest tests/test_packaging.py tests/test_tangle_cli_cli.py (6 passed)
• uv build
• uv build --package tangle-api
• local release smoke tests for root wheel/sdist (tangle version, tangle-cli version)
• local tangle-api wheel/sdist import/version smoke tests
• local tangle-cli[native] resolution against built dist/ artifacts

Release notes

This PR prepares publishing only. It does not publish to PyPI. A later release tag such as v0.0.1a2 will trigger the workflow.

Prerelease caveat: top-level installs from an index may still need an exact prerelease spec and/or prerelease allowance until a stable version exists. Exact transitive prerelease pins should resolve once the selected tangle-cli==0.0.1a2 prerelease is allowed/selected.

[Volv-G]

• fix: prepare prerelease packages for PyPI #9 👈 (View in Graphite)
• master

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