👷 add Release job for bumping version

[guimorg]

Note

Medium Risk
Adds an automated release workflow that pushes commits directly to main with contents: write, which can affect versioning/history if misconfigured. Also updates GitHub Actions dependencies, which is low risk but impacts CI execution.

Overview
Updates the main CI workflow to use actions/checkout@v6 and pins astral-sh/setup-uv to the v8.0.0 commit for reproducible builds.

Adds a new Release workflow that runs on release.published, bumps the project version via uv version from the tag name, then commits and pushes the updated pyproject.toml and uv.lock back to main (with [skip ci]).

^{Written by Cursor Bugbot for commit 03ced35. This will update automatically on new commits. Configure here.}

[cursor]

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

^{Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}