The status is shown for
- The author of a commit when viewing a commit
- Notes on a commit (regular/diff)
- The user that triggered a pipeline when viewing a pipeline
- The author of a merge request when viewing a merge request
- The author of notes on a merge request (regular/diff)
- The author of an issue when viewing an issue
- The author of notes on an issue
- The author of a snippet when viewing a snippet
- The author of notes on a snippet
- A user's profile page
- The list of members of a group/user

With text/calendar as Content-Type, the browser always downloads the
content as a file (even ignoring the Content-Disposition header). We
want to display the content inline when accessed from GitLab, similarly
to the RSS feed.

This could only be possible for users that can create merge requests
within a project.

So they need to be a allowed to create a branch and create a merge request.

So we can distinguish between the permissions on the source and the
target project.

- `create_merge_request_from` indicates a user can create a merge
  request with the project as a source_project
- `create_merge_request_in` indicates a user can create a merge
  request with the project as a target_project

By extracting a new `filter_items` method, we can override that in the
IssuesFinder and MergeRequestsFinder separately, so we don't need checks that
the model is the correct one, because we can just use the class we're in to know
that.

We can do the same for the VALID_PARAMS constant, by making it a class method.

Closes #26466.

This ensures that we have more visibility in the number of SQL queries
that are executed in web requests. The current threshold is hardcoded to
100 as we will rarely (maybe once or twice) change it.

In production and development we use Sentry if enabled, in the test
environment we raise an error. This feature is also only enabled in
production/staging when running on GitLab.com as it's not very useful to
other users.

Adds a rubocop rule (with autocorrect) to ensure line break after guard clauses.

This reverts commit 915e35a2, reversing
changes made to 9533786f.

Discussions are now done asynchronously via the `IssuesController#discussions`
endpoint, so this should no longer be needed. This was taking 32% of the load
time for GitLab CE issue 1.

Closes #38034

In #37955,we see that the profile had a number of N+1 queries from repeated
access to `cross_reference_not_visible_for?`. This was optimized in previous
versions of GitLab by rendering all notes at once, counting the number of
visible references, and then using that number to check whether a system note
should be fully redacted.

There was also another N+1 query calling `ProjectTeam#member?`, which did not
take advantage of an optimization in prepare_notes_for_rendering that would
preload the maximum access level per project.

Closes #37955

This makes it easier to reuse in EE.

this will remove the need make N queries (per-note) at the
cost of having to mark notes with an attribute

this opens up the possibility for other special roles for notes

This changes the issue and MR index pages so the pagination system
re-uses the output of the COUNT(*) query used to calculate the number of
rows per state (opened, closed, etc). This removes the need for an
additional COUNT(*) on both pages.

Fix https://gitlab.com/gitlab-org/gitlab-ce/issues/34261

Its usage has been removed at 2fa22a07.

This reverts merge request !12633