Move the object types REST API endpoint to the `core` app

[jeremystretch]

NetBox version

v4.3.3

Feature type

Change to existing functionality

Proposed functionality

Move the REST API endpoint for object types from /api/extras/object-types/ to /api/core/object-types/. We can implement a redirect at the old endpoint to ensure backward compatibility.

(This FR was prompted by FR #19722.)

Use case

The current endpoint is outdated; it was originally implemented to serve Django's native ContentType model. However, in recent releases ObjectType, a proxy model within NetBox's core app, has superseded ContentType, and the REST API endpoint should be moved to reflect this.

Database changes

N/A

External dependencies

N/A