- Replaced the internal `_expand_vlan_range` function in the `Qtech` class with the new `expand_vlan_range` utility from `utils.py` for improved code maintainability.
- Added new configuration files `config_1.conf` and `config_2.conf` for Qtech devices to facilitate testing.
- Introduced expected output JSON files `config_1.expected.json` and `config_2.expected.json` to validate the parsing of Qtech configurations against expected results.
