Alpine Linux — Publish to Alpine package repository

Publish clitest as Alpine Linux package (apk).

## Use cases
- Alpine-based Docker images (common in CI)
- Lightweight Linux environments
- `apk add clitest` in Dockerfiles

## Steps
1. Create APKBUILD file
2. Submit to Alpine aports (community repo)
3. Requires stable releases + open-source license

## Open questions
- Priority vs. Homebrew tap?
- Alpine testing repo first, then community?