Remove release workflow (#10)

The release workflow is not needed when creating releases through
GitHub's UI. The workflow was failing because:

1. Creating a release in GitHub UI automatically creates the tag
2. The tag creation triggers the workflow
3. The workflow tries to create a release that already exists

Since releases are being created manually through the UI, this
workflow adds no value and only causes confusion with failures.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-authored-by: Claude <[email protected]>

Author: imjasonh