- Made normalize_mac/1 public with comprehensive documentation
- Enhanced normalize_mac to handle:
- Binary MAC addresses (6 bytes) with proper hex conversion
- Short MAC addresses with zero-padding (e.g., 'A:B' -> '0a:0b')
- Colons, dashes, and no-separator formats
- Fixed refresh_links_for_device/1 to return :ok when device not found
(was returning nil, causing test failures)
- Fixed site fallback test to use assigned_network_site_gaiia_id
(string field) instead of network_site_id (FK)
- Simplified account lookup optimization test to remove
non-existent Repo.query_count/1 dependency
All 19 subscriber matching tests now passing:
- 7 normalize_mac/1 tests (binary, colons, dashes, padding, etc.)
- 12 refresh_device_links/1 tests (all match methods, prioritization,
cross-org isolation, etc.)
