chore(release): authenticate git pushes with deploy key

[alexb-splunk]

Summary

• configure the semantic-release checkout to use the protected RELEASE_DEPLOY_KEY environment secret
• keep GH_TOKEN for GitHub API operations while using SSH for release commit and tag pushes
• avoid exposing the deploy key to the preliminary release-check job
• exclude non-versioning Conventional Commit types from changelog output while preserving release-affecting and breaking commits

Validation

• git diff --check
• parsed pyproject.toml with Python tomllib
• validated changelog exclusion patterns against bumping, non-bumping, and breaking commit examples
• loaded the semantic-release configuration in no-operation mode
• parsed the GitHub Actions workflow as YAML
• verified actions/checkout@v7 supports the ssh-key input
• uv run tox -e lint,format

Release procedure

The Main ruleset now allows Deploy keys to bypass with Always allow. Merging this PR will trigger a fresh release workflow; approve the pypi environment deployment to publish v1.1.0.

The previously failed workflow should not be rerun because it uses the old workflow definition.