[COMMS-850] handle target/observed versions in project copy

[brunopagno]

Ticket

https://community.openproject.com/wp/COMMS-850

What are you trying to accomplish?

• When copying a project it copies target_versions and observed_in_versions as well
• When copying a project it still copies versions the same way as before
• When copying a project and not including versions, it works as well

Screenshots

Videocaptura.de.pantalla_20260703_142445.webm

Merge checklist

• Added/updated tests
• Added/updated documentation in Lookbook (patterns, previews, etc)
• Tested major browsers (Chrome, Firefox, Edge, ...)

[github-actions]

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