RUN AS-IF-FOSS Move deploy boards backend to core

What does this MR do?

Part one of moving deploy boards to core:

• Move EE model components into their core equivalent
• Move EE lib/ concepts to core

Deploy boards as a feature are unchanged (still EE-only).

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Related to #212320 (closed)