Context Id History for imported in course archives

MDL-69502 introduced the support for context id history, that is, the context id chains of the Moodle courses from which this context is a copy from.

However this 1st implementation only covers new courses created off course archives. If an archive is imported in an existing course, then the history does not reflect this.

The proposal of this change would be to expose in the context id history the ids of all course archives that were imported in the current moodle course, becoming a multi-lineage history (i.e. one course may have multiple ancestors if it was built from more than one course archive).