[codex] Drive changelog releases from towncrier

[adamtheturtle]

Summary

This switches release changelog handling to the same towncrier-based flow used by literalizer:

• replace the manual Next changelog section update with towncrier build
• generate GitHub release notes from the same news fragments
• add the towncrier config, template, and newsfragments/ directory
• render unreleased fragments in docs where the project has Sphinx docs
• migrate any existing Next entries into initial news fragments

Validation

• uv run --extra=release towncrier build --draft --version 2099.01.01
• uvx --from actionlint-py actionlint .github/workflows/release.yml
• uv run --extra=dev pyproject-fmt --check --no-print-diff pyproject.toml where the repo has a dev extra
• repo pre-commit / pre-push hooks run by git commit and git push

---

Note

Medium Risk
Release automation now builds both CHANGELOG.rst and GitHub release bodies from Towncrier fragments, which can affect tagging/publishing if the new workflow or templates mis-render or fail in CI.

Overview
Switches the release workflow from manually editing a Next section to running towncrier build to both generate GitHub release notes (bodyFile: release-notes.md) and update CHANGELOG.rst, committing the consumed newsfragments/ in the same bump commit.

Adds Towncrier into the project via new [tool.towncrier] config and a custom template (docs/towncrier_template.rst.jinja), introduces an unreleased docs page rendered from draft fragments during Sphinx builds (sphinxcontrib.towncrier.ext), and updates manifest tooling to ignore newsfragments/**.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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Towncrier not in release extra, workflow will fail

High Severity

The workflow runs uv run --extra=release towncrier build but towncrier is only declared under optional-dependencies.dev, not optional-dependencies.release (which only contains check-wheel-contents). On a clean CI runner, uv will only install the release extra's dependencies, so the towncrier CLI won't be available and both changelog steps will fail.

Additional Locations (1)

• pyproject.toml#L88-L89

 

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