Generated the changelog entry

#30526 (A) [BE] Wiki Events (models)

See merge request gitlab-org/gitlab!26529

Unpublish details for confidential issues

See merge request gitlab-org/gitlab!27263

Renames the ProjectMetrics to name the team uses CustomMetrics

See merge request gitlab-org/gitlab!27433

Move tests of BaseField description to be sibling of "complexity" context

See merge request gitlab-org/gitlab!27297

Add docs to describe praefect failover

Closes gitaly#2472

See merge request gitlab-org/gitlab!27242

Docs: Document redirect option for container registry

See merge request gitlab-org/gitlab!27413

Add note to documentation on how to enable the `redirect` option
for the container registry.

Add info on CI/CD variable encryption

See merge request gitlab-org/gitlab!27503

Update comment in troubleshooting example

See merge request gitlab-org/gitlab!27474

Clarify when user can be deactivated

See merge request gitlab-org/gitlab!27491

Docs: Permission denied errors when clock drift on Gitaly standalone

See merge request gitlab-org/gitlab!27550

Added Sidekiq setup documentation

See merge request gitlab-org/gitlab!25486

Resolve "Improve format support message in issue design"

See merge request gitlab-org/gitlab!27409

Add option for switching between block log

See merge request gitlab-org/gitlab!27133

Modes can be either logging
and blocking in addition to
enabling or disabling Modsecurity

Replace underscore/lodash in ee/analytics

Closes #210254

See merge request gitlab-org/gitlab!27146

Protect against nil metric identifier

Closes #207457

See merge request gitlab-org/gitlab!27461

Merge branch '39275-step-4-be-version-control-for-snippets-implement-git-actions-in-the-view-mvp' into 'master'

Resolve "Step 4 (BE): Version Control for Snippets: Implement git actions in the view (MVP)"

Closes #39275

See merge request gitlab-org/gitlab!26640

Merge branch '210259-replace-underscore-with-lodash-for-ee-app-assets-javascripts-dependencies' into 'master'

Replace underscore with lodash for ./ee/app/assets/javascripts/dependencies

Closes #210259

See merge request gitlab-org/gitlab!27312

Refactor some Geo Node tests with vue-test-utils

See merge request gitlab-org/gitlab!27150

Geo Node Form in Vue - API/Validations

Closes #118841

See merge request gitlab-org/gitlab!25851

Snippet repositories will be phased in. Currently endpoint URLs are
dependent on the snippet itself being attached to a repository, and the
version_snippet feature flag setting.

Update code_quality.md with correct link to code climate spec.

See merge request gitlab-org/gitlab!27385

Fix repmgr restore steps to avoid subsequent failures

See merge request gitlab-org/gitlab!27548

Unquarantine tests that use deploy keys

Closes #208761

See merge request gitlab-org/gitlab!27465

Prune Rails Console cheat sheet

Closes gitlab-com/support/toolbox/snippets#38, gitlab-com/support/toolbox/snippets#31, gitlab-com/support/toolbox/snippets#26, gitlab-com/support/toolbox/snippets#22, gitlab-com/support/toolbox/snippets#21, gitlab-com/support/toolbox/snippets#20, and gitlab-com/support/toolbox/snippets#3

See merge request gitlab-org/gitlab!27523

Doc for making hostname configurable for smartcard authentication

See merge request gitlab-org/gitlab!27000

Handle errors with repos api

See merge request gitlab-org/gitlab!27426

Docs: descriptions and comments 1m-char limit

Closes #31148

See merge request gitlab-org/gitlab!27339

this was only ever needed in tests, and having it on the actual
wiki-page model is just incurring technical debt and installing a
permanent footgun. It is removed and replaced with factories.

This also refactors the event spec to be much more declarative for
visibility tests.

This removes the DB timestamp column defaults, and manages those values
in the model domain object instead.

This adds validations that ensure that wiki pages cannot have the same
canonical slug in the same project. We cannot easily move this check to
the DB, so this is handled in logic - we check in `.find_or_create` if
either of the known slugs matches a record, and we raise errors on
conflict.

This also introduces some optimisations that eliminate unnecessary
queries.

Minor updates from review comments

Includes:

- Use Class#name instead of constant
- Wrap mutable state in an outer transaction

  The one subtle thing here is that the first query (to find the record)
  must be within the transaction, even though it does not mutate the state
  of the DB. This is because we learn important facts from that query
  (namely whether there are any conflicting canonical slugs) that could be
  invalidated outside a transaction.

- Use standard uniqueness validator

  This is more declarative than our hand-rolled implementation

- Move page construction into factory

  This requires a new trait for the wiki page factory to create pages that
  are in the wiki repo.

- Changes to some test descriptions

- Reduce DB queries in specs

we don't strictly need multiple slugs here - one will do.

- Avoid running validation if there is no project_id

- Raise error if there are no slugs at all