This service is required for implementing Approvals for CE

This service is required for implementing Approvals for CE

This change is part of
https://gitlab.com/gitlab-org/gitlab/-/issues/212566 to move all Design
Management code to FOSS.

This MR moves model code that references parts of Design Management. The
"core" Design Management model code has been moved in
https://gitlab.com/gitlab-org/gitlab/-/merge_requests/30015.

Create system note when issue health status is updated

When picking a merge_commit, it will be annotated with a system note.

This feature is behind the :track_mr_picking feature flag

- Include new types in SystemNoteMetadata
- Add Label and Milestone reference_pattern to
Mentionable::ReferenceRegexes to be checked for cross references

Also associates the version to the system note that
logs the change

All instances of injecting an EE specific module have been changed to
use the new methods for this: prepend_if_ee, extend_if_ee, and
include_if_ee. This allows these lines to be included in CE, even when
the modules to inject do not exist. This in turn allows us to backport
these lines to CE and keep them there, instead of having to strip them
out.

Add a zoom link added / removed system note when a zoom link is being
added / removed to the issue description.

This moves all instances of `prepend EE::Something` and `include
EE::Something` in models to the last line of the corresponding model.
This pushes EE specific code further down the files, reducing the
likelihood of developers running into merge conflicts.

Partially addresses #47424.

Partially addresses #47424.

Signed-off-by: Rémy Coutable <remy@rymai.me>

EE port of https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/12845

Marking an issue as a duplicate will now also add an upvote on behalf of the author on the original issue.

This reverts commit b34bc6fe, reversing
changes made to e9fcae37.