This pull request reorganizes and modernizes the Manufacturing app’s internal structure to prepare for upcoming production planning improvements. Most changes are behind the scenes, helping make future manufacturing, repair, byproduct, and operations updates cleaner and easier to maintain.

This update restructures manufacturing-related code and moves equipment maintenance into clearer module areas, aligning it with newer Odoo development standards. Business users should see little direct workflow change, but the cleanup helps make future manufacturing, repair, and maintenance improvements easier and safer to deliver.

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:
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