The base_gengo module was reorganized into a cleaner file structure and updated to Odoo's newer development framework. This should make the translation service integration easier to maintain without changing day-to-day user workflows.

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:
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The Gengo translation integration was reorganized and updated to work with Odoo's newer internal framework. This helps keep automated translation features maintainable and compatible without changing the core business workflow.

- Task : https://www.odoo.com/web#id=12209&view_type=form&model=project.task&menu_id=3942&action=327
- Pad : https://pad.odoo.com/p/r.4YJMn6R8itJDcfnQ

The module import feature was updated to use Odoo's newer internal framework. This keeps the tool maintainable and compatible with the latest platform standards without changing the business workflow.

Task: https://www.odoo.com/web?#id=12346&view_type=form&model=project.task&action=327
Pad: https://pad.odoo.com/p/r.qLBqdiKpoSjcFVeO