Build and publish cx-ops .deb package

## Summary
Package cx-ops Python module as .deb for apt repository.

## Requirements
- Build workflow for cx-ops (doctor, diagnostics, repair tools)
- Package name: cx-ops
- Dependencies: cx-core, python3-psutil

## Acceptance Criteria
- [ ] `apt install cx-ops` works
- [ ] `cx doctor` functional after install
- [ ] Health checks run successfully